feature

The International HapMap Project
The International HapMap Consortium**Lists of participants and affiliations appear at the end of the paper...........................................................................................................................................................................................................................

The goal of the International HapMap Project is to determine the common patterns of DNA sequence variation in the human genome
and to make this information freely available in the public domain. An international consortium is developing a map of thesepatterns across the genome by determining the genotypes of one million or more sequence variants, their frequencies and thedegree of association between them, in DNA samples from populations with ancestry from parts of Africa, Asia and Europe. The
HapMap will allow the discovery of sequence variants that affect common disease, will facilitate development of diagnostic tools,
and will enhance our ability to choose targets for therapeutic intervention.

Common diseases such as cardiovascular disease, cancer,
obesity, diabetes, psychiatric illnesses and inflammatory
diseases are caused by combinations of multiple genetic
and environmental factors1. Discovering these genetic
factors will provide fundamental new insights into thepathogenesis, diagnosis and treatment of human disease. Searches
for causative variants in chromosome regions identified by linkage
analysis have been highly successful for many rare single-gene
disorders. By contrast, linkage studies have been much less successful in locating genetic variants that affect common complex diseases, as each variant individually contributes only modestly todisease risk2,3. A complementary approach to identifying these
specific genetic risk factors is to search for an association between
a specific variant and a disease, by comparing a group of affectedindividuals with a group of unaffected controls4. In the absence ofstrong natural selection, there is likely to be a broad spectrum of
frequency of such variants, many of which are likely to be common
in the population. A number of association studies, focused on
candidate genes, regions of linkage to a disease or more large-scale
surveys, have already led to the discovery of genetic risk factors forcommon diseases. Examples include type 1 diabetes (humanleukocyte antigen (HLA5), insulin6 and CTLA4 (ref. 7)), Alzheimer’s
disease (APOE)8, deep vein thrombosis (factor V)9, inflammatory
bowel disease (NOD2 (refs 10, 11) and also 5q31 (ref. 12)),hypertriglyceridaemia (APOAV)13, type 2 diabetes (PPARG)14,15,
schizophrenia (neuregulin 1)16 , asthma (ADAM33)17 , stroke(PDE4D)18 and myocardial infarction (LTA)19.
One approach to doing association studies involves testing eachputative causal variant for correlation with the disease (the ‘direct’approach)2. To search the entire genome for disease associations
would entail the substantial expense of whole-genome sequencing
of numerous patient samples to identify the candidate variants3. At
present, this approach is limited to sequencing the functional partsof candidate genes (selected on the basis of a previous functional or
genetic hypothesis) for potential disease-associated candidate variants. An alternative approach (the ‘indirect’ approach) has been
proposed20, whereby a set of sequence variants in the genome could
serve as genetic markers to detect association between a particulargenomic region and the disease, whether or not the markers
themselves had functional effects. The search for the causative
variants could then be limited to the regions showing association
with the disease.
Two insights from human population genetics suggest that theindirect approach is able to capture most human sequence variation, with greater efficiency than the direct approach. First, ,90%of sequence variation among individuals is due to common variants21. Second, most of these originally arose from single historicalmutation events, and are therefore associated with nearby variants
that were present on the ancestral chromosome on which themutation occurred. These associations make the indirect approach
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feasible to study variants in candidate genes, chromosome regions
or across the whole genome. Prior knowledge of putative functionalvariants is not required. Instead, the approach uses informationfrom a relatively small set of variants that capture most of
the common patterns of variation in the genome, so that any
region or gene can be tested for association with a particular disease,with a high likelihood that such an association will be detectable if itexists.
The aim of the International HapMap Project is to determine thecommon patterns of DNA sequence variation in the humangenome, by characterizing sequence variants, their frequencies,and correlations between them, in DNA samples from populations
with ancestry from parts of Africa, Asia and Europe. The project willthus provide tools that will allow the indirect association approach
to be applied readily to any functional candidate gene in the
genome, to any region suggested by family-based linkage
analysis, or ultimately to the whole genome for scans for diseaserisk factors.
Common variants responsible for disease risk will be most readily
approached by this strategy, but not all predisposing variants arecommon. However, it should be noted that even a relatively
uncommon disease-associated variant can potentially be discovered
using this approach. Reflecting its historical origins, the uncommon
variant will be travelling on a chromosome that carries a characteristic pattern of nearby sequence variants. In a group of people
affected by a disease, the rare variant will be enriched in frequency
compared with its frequency in a group of unaffected controls. Thisobservation, for example, was of considerable assistance in theidentification of the genes responsible for cystic fibrosis22 anddiastrophic dysplasia23, after linkage had pointed to the generalchromosomal region.
Below we provide a brief description of human sequence variation, and then describe the strategy and key components of the
project. These include the choice of samples and populations forstudy, the process of community engagement or public consultation, selection of single-nucleotide polymorphisms (SNPs), genotyping, data release and analysis.

Human DNA sequence variation
Any two copies of the human genome differ from one another byapproximately 0.1% of nucleotide sites (that is, one variant per
1,000 bases on average)24–27. The most common type of variant, a
SNP, is a difference between chromosomes in the base present at aparticular site in the DNA sequence (Fig. 1a). For example, somechromosomes in a population may have a C at that site (the ‘Callele’), whereas others have a T (the ‘Tallele’). It has been estimatedthat, in the world’s human population, about 10 million sites (thatis, one variant per 300 bases on average) vary such that both alleles
are observed at a frequency of $1%, and that these 10 million
common SNPs constitute 90% of the variation in the popu-© 2003 Nature Publishing Group789

feature
lation21,28. The remaining 10% is due to a vast array of variants thatare each rare in the population. The presence of particular SNP
alleles in an individual is determined by testing (‘genotyping’) a
genomic DNA sample.
Nearly every variable site results from a single historical mutational event as the mutation rate is very low (of the order of 1028 persite per generation) relative to the number of generations since themost recent common ancestor of any two humans (of the order of
104 generations). For this reason, each new allele is initiallyassociated with the other alleles that happened to be present on
the particular chromosomal background on which it arose. The
specific set of alleles observed on a single chromosome, or part of achromosome, is called a haplotype (Fig. 1b). New haplotypes areformed by additional mutations, or by recombination when thematernal and paternal chromosomes exchange corresponding segments of DNA, resulting in a chromosome that is a mosaic of thetwo parental haplotypes29.
The coinheritance of SNP alleles on these haplotypes leads toassociations between these alleles in the population (known as
linkage disequilibrium, LD). Because the likelihood of recombination between two SNPs increases with the distance between them, on
average such associations between SNPs decline with distance.
Many empirical studies have shown highly significant levels ofLD, and often strong associations between nearby SNPs, in thehuman genome30–34. These strong associations mean that in many
chromosome regions there are only a few haplotypes, and theseaccount for most of the variation among people in thoseregions31,35,36.
The strong associations between SNPs in a region have a practicalvalue: genotyping only a few, carefully chosen SNPs in the region
will provide enough information to predict much of the information about the remainder of the common SNPs in that region. As
a result, only a few of these ‘tag’ SNPs are required to identify each of

the common haplotypes in a region35,37–39 (Fig. 1c).
As the extent of association between nearby markers varies
dramatically across the genome30–32,34,35,40, it is not efficient to use
SNPs selected at random or evenly spaced in the genome sequence.
Instead, the patterns of association must be empirically determinedfor efficient selection of tag SNPs. On the basis of empirical studies,it has been estimated that most of the information about genetic
variation represented by the 10 million common SNPs in the
population could be provided by genotyping 200,000 to 1,000,000
tag SNPs across the genome31,36,38,39. Thus, a substantial reduction in
the amount of genotyping can be obtained with little loss of
information, by using knowledge of the LD present in the genome.
For common SNPs, which tend to be older than rare SNPs, thepatterns of LD largely reflect historical recombination and demographic events41. Some recombination events occur repeatedly at‘hotspots’30,42. The result of these processes is that current chromosomes are mosaics of ancestral chromosome regions29. This explains
the observations that haplotypes and patterns of LD are shared byapparently unrelated chromosomes within a population and generally among populations43.
These observations are the conceptual and empirical foundation
for developing a haplotype map of the human genome, the‘HapMap’. This map will describe the common patterns of variation, including associations between SNPs, and will include the tag
SNPs selected to most efficiently and comprehensively capture thisinformation.

Figure 1 SNPs, haplotypes and tag SNPs. a, SNPs. Shown is a short stretch of DNA
from four versions of the same chromosome region in different people. Most of the DNA
sequence is identical in these chromosomes, but three bases are shown where
variation occurs. Each SNP has two possible alleles; the first SNP in panel a has thealleles C and T. b, Haplotypes. A haplotype is made up of a particular combination ofalleles at nearby SNPs. Shown here are the observed genotypes for 20 SNPs that
extend across 6,000 bases of DNA. Only the variable bases are shown, including thethree SNPs that are shown in panel a. For this region, most of the chromosomes in a
population survey turn out to have haplotypes 1–4. c, Tag SNPs. Genotyping just thethree tag SNPs out of the 20 SNPs is sufficient to identify these four haplotypes
uniquely. For instance, if a particular chromosome has the pattern A–T–C at thesethree tag SNPs, this pattern matches the pattern determined for haplotype 1. Note thatmany chromosomes carry the common haplotypes in the population.

790

The International HapMap Consortium
An initial meeting to discuss the scientific and ethical issues
associated with developing a human haplotype map was held in
Washington DC on 18–19 July 2001 (http://www.genome.gov/
10001665). Groups were organized to consider the ethical issues,
to develop the scientific plan and to choose the populations to© 2003 Nature Publishing Group

NATURE | VOL 426 | 18/25 DECEMBER 2003 | www.nature.com/naturefeature
include. The International HapMap Project (http://www.hapmap.
org/) was then formally initiated with a meeting in Washington DC
on 27–29 October 2002 (http://www.genome.gov/10005336). The
participating groups and funding sources are listed in Table 1.

DNA samples and populations
Human populations are the products of numerous social, historicaland demographic processes. As a result, no populations are typical,
special or sharply bounded44,45. As most common patterns ofvariation can be found in any population46, no one population isessential for inclusion in the HapMap. Nonetheless, we decided toinclude several populations from different ancestral geographic
locations to ensure that the HapMap would include most of thecommon variation and some of the less common variation indifferent populations, and to allow examination of various hypotheses about patterns of LD.
Studies of allele frequency distributions suggest that ancestralgeography is a reasonable basis for sampling human populations44,47,48. Pilot studies using samples from the Yoruba, Japanese,
Chinese and individuals with ancestry from Northern and Western
Europe have shown substantial similarity in their haplotype patterns, although the frequencies of haplotypes often differ31,44. Given
these scientific findings, coupled with consideration of ethical,
social and cultural issues, these populations were approached forinclusion in the HapMap through a process of community engagement or consultation (see Box 1).
The HapMap developed with samples from these four large

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populations will include a substantial amount of the genetic
variation found in all populations throughout the world. The goalof the HapMap is medical, and the common patterns of variation
identified by the project will be useful to identify genes that
contribute to disease and drug response in many other populations.
Samples from several other populations are being collected forstudies that will examine how similar their haplotype patterns are to
those in the HapMap. If the patterns found are very different,
samples from some of these populations may be genotyped on alarge scale to make the HapMap more applicable to them. Further
follow-up studies in other populations, small and large, are likely to
be undertaken by scientists in many nations for common diseasegene discovery.
The project will study a total of 270 DNA samples: 90 samples (seeSupplementary Information, part 1) from a US Utah population
with Northern and Western European ancestry (samples collected in1980 by the Centre d’Etude du Polymorphisme Humain (CEPH)49
and used for other human genetic maps, 30 trios of two parents andan adult child), and new samples collected from 90 Yoruba people in
Ibadan, Nigeria (30 trios), 45 unrelated Japanese in Tokyo, Japan,
and 45 unrelated Han Chinese in Beijing, China. All donors gave
specific consent for their inclusion in the project. Population
membership was determined in ways appropriate for each culture:
for the Yoruba by asking the donor whether all four grandparents
were Yoruba, for the Han Chinese by asking the donor whether at
least three of four grandparents were Han Chinese, and for theJapanese by self-identification. The CEPH samples are available© 2003 Nature Publishing Group791

featurefrom the non-profit Coriell Institute of Medical Research (http://locus.umdnj.edu/nigms/); cell lines and DNA from the new samples
will be available from Coriell in early 2004 for future studies withresearch protocols approved by appropriate ethics committees. It is
anticipated that other researchers will genotype additional SNPs inthese samples in the future, and that these data will continuously
improve the HapMap.
These samples will have population and sex identifiers without
information that could link them to individual donors. As thegoal of the project is solely to identify patterns of genetic variation,
no medical or other phenotypic information will be included.
About 50% more samples were collected than will be used, sothat inclusion of a sample from any particular donor cannot beknown.
Samples of 45 unrelated individuals should be sufficient to find
99% of haplotypes with a frequency of 5% or greater in a population. Studies of LD can use random individual samples, trios orlarger pedigrees; each design has advantages (ease of sampling) anddisadvantages (decreasing efficiency with increasing numbers ofrelated individuals). Analysis of existing data and computer simulations suggested that unrelated individuals and trios have considerable power for estimating local LD patterns. The trios will
provide useful information on the accuracy of the genotyping
platforms being used for the project.

Choice of SNPs
A high density of SNPs is needed to describe adequately the genetic
variation across the entire genome. When the project started, theaverage density of markers in the public database dbSNP (http://
www.ncbi.nlm.nih.gov/SNP/)50 was approximately one every kilobase (2.8 million SNPs) but, given their variable distribution, many
regions had a lower density of SNPs.
Further SNPs were obtained by random shotgun sequencing
from whole-genome and whole-chromosome (flow-sorted)
libraries51, using methods developed for the initial human SNP
map52, and also by collaboration with Perlegen Sciences36 andthrough the purchase of sequence traces from Applied Biosystems53
for SNP detection (see Supplementary Information, part 2). One
useful result of this search for more SNPs is the confirmation of
SNPs found previously. SNPs for which each allele has been seen
independently in two or more samples (‘double-hit’ SNPs) have ahigher average minor allele frequency than do ‘single-hit’ SNPs28.
This leads to substantial savings in assay development. On 4
November 2003, the number of SNPs (with a unique genomic
position) in dbSNP (build 118) was 5.7 million, and the number ofdouble-hit SNPs was over 2 million. By February of 2004, 6.8
million SNPs (with a unique genomic position) are expected to
be in dbSNP and available for the project, including 2.7 million
double-hit SNPs.
As the extent of LD and haplotypes varies by 100-fold across the
genome30–32,34,35, a hierarchical genotyping strategy has been
adopted. In an initial round of genotyping, the project aims togenotype successfully 600,000 SNPs spaced at approximately 5-kilobase intervals and each with a minor allele frequency of at least 5%,
in the 270 DNA samples. Priority is being given to previously
validated SNPs, double-hit SNPs and SNPs causing amino-acidchanges (as these may alter protein function). When these genotyping data are produced (by mid-2004; see below for details of data
release), they will be analysed for associations between neighbouring SNPs. Additional SNPs will then be genotyped in the same DNA
samples at a higher density only in regions where the associations
are weak. Further rounds of analysis and genotyping will be carriedout as required. It is expected that more than one million SNPs will
be genotyped overall. This hierarchical strategy will permit regionsof the genome with the least LD to be characterized at densities of up
to one SNP per kilobase, maximizing the characterization of regionswith associations only over short distances.
792

Genotyping
Each genotyping centre is responsible for genotyping all the samples
for all the selected SNPs on the chromosome regions allocated(Table 1). Among the centres, a total of five high-throughput
genotyping technologies are being used, which will provide an
opportunity to compare their accuracy, success rate, throughput
and cost. Access to several platforms is an advantage for the project,
as a SNP assay that fails on one platform may be developed
successfully using another method in order to fill a gap in the
HapMap. All platforms will be evaluated using a common set of
performance criteria to ensure that the quality of data produced forthe project meets a uniformly high standard.
Genotype quality is being assessed in three ways. First, at the
beginning of the project, all centres were assigned the samerandomly selected set of 1,500 SNPs for assay development andgenotyping in the 90 CEPH DNA samples being used for the project.
Genotyping centres produced data that were on average more than
99.2% complete and more than 99.5% accurate (as compared to theconsensus of at least two other platforms). Second, every genotyping experiment includes samples for internal quality checks, witheach 96-well plate containing duplicates of five different samples,and one blank. In addition, the data from trios provide a check forconsistent mendelian inheritance of SNP alleles. For all the populations, the data from the unrelated samples provide a check that the
SNPs are in Hardy–Weinberg equilibrium (a test of genetic mating

Box 1
Community engagement, public consultation andindividual consent
As no personally identifiable information will be linked to the samples,
the risk that an individual will be harmed by a breach of privacy, or bydiscrimination based on studies that use the HapMap, is minimal.
However, because tag SNPs for future disease studies will be chosenon the basis of haplotype frequencies in the populations included in
the HapMap, the data will be identified as coming from one of the four
populations involved, and it will be possible to make comparisons
between the populations. As a result, the use of population identifiers
may create risks of discrimination or stigmatization, as might occur if ahigher frequency of a disease-associated variant were to be found in agroup and this information were then overgeneralized to all or most ofits members64. It is possible that there are other culturally specific risks
that may not be evident to outsiders65. To identify and address thesegroup risks, a process of community engagement, or public
consultation, was undertaken to confer with members of the
populations being approached for sample donation about the
implications of their participation in the project66,67. The goal was togive people in the localities where donors were recruited theopportunity to have input into the informed consent and sample
collection processes, and into such issues as how the populations
from which the samples were collected would be named. Community
engagement is not a perfect process, but it is an effort to involve
potential donors in a more extended consideration of the implicationsof a research project before being asked to take part in it68.
Community engagement and individual informed consent wereconducted under the auspices of local governments and ethics
committees, taking into account local ethical standards andinternational ethical guidelines. As in any cross-cultural endeavour, theform and outcome of the processes varied from one population toanother. A Community Advisory Group is being set up for each
community to serve as a continuing liaison with the sample repository,
to ensure that future uses of the samples are consistent with the uses
described in the informed consent documents. A more detailed article
discussing ethical, social and cultural issues relevant to the project,and describing the processes used to engage donor populations in
identifying and evaluating these issues, is in preparation.

© 2003 Nature Publishing Group

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patterns). Although a small proportion of SNPs may fail thesechecks for biological reasons, they more typically fail if a genotyping
platform makes consistent errors, such as undercalling heterozygotes. Third, a sample of SNP genotypes deposited by each centre
will be selected at random and re-genotyped by other centres. These
stringent third-party evaluations of quality will ensure thecompleteness and reliability of the data produced by the project.

Data release
The project is committed to rapid and complete data release, and toensuring that project data remain freely available in the publicdomain at no cost to users. The project follows the data-releaseprinciples of a ‘community resource project’ (http://www.wellcome.
ac.uk/en/1/awtpubrepdat.html).
All data on new SNPs, assay conditions, and allele and genotype
frequencies will be released rapidly into the public domain on theinternet at the HapMap Data Coordination Center (DCC) (http://
www.hapmap.org/) and deposited in dbSNP. Individual genotype
and haplotype data initially will be made available at the DCC undera short-term ‘click-wrap’ licence agreement. This strategy has been
adopted to ensure that data from the project cannot be incorporated
into any restrictive patents, and will thus remain freely available in
the long term. The only condition for data access is that users must
agree not to restrict use of the data by others and to share the data
only with others who have agreed to the same condition. When
haplotypes are defined in a region, then the individual genotypes,
haplotypes and tag SNPs in that region will be publicly released to
dbSNP, where there are no licensing conditions. Project participants
have agreed that their own laboratories will access the data throughthe DCC and under the click-wrap licence, ensuring that allscientists have equal access to the data for research.
The consortium believes that SNP, genotype and haplotype datain the absence of specific utility do not constitute appropriately
patentable inventions. Specific utility would involve, for example,
finding an association of a SNP or haplotype with a medicallyimportant phenotype such as a disease risk or drug response. The
project does not include any phenotype association studies. However, the data-release policy does not block users from filing for
appropriate intellectual property on such associations, as long as
any ensuing patent is not used to prevent others’ access to the
HapMap data.

Data analysis
The project will apply existing and new methods for analysis anddisplay of the data. LD between pairs of markers will be calculatedusing standard measures such as D 0 (ref. 54), r 2 (refs 55, 56) andothers. Various methods are being evaluated to define regions ofhigh LD and haplotypes along chromosomes. Existing methods
include ‘sliding window’ LD profiles57,58, LD unit maps59, haplotype
blocks31,35 and estimates of meiotic recombination rates along
chromosomes35,60–62. After analysis of the LD in the first phase of
the project, regions in which there is little or no LD will be identified
and ranked for further SNP selection and genotyping. Methods toselect optimal collections of tag SNPs will be developed andevaluated (see above). The project will thus provide views of thedata and tag SNPs that will be useful to the research community. As
all data and analysis methods will be made available, other researchers will also be able to analyse the data and improve the analysis
methods.
To assist optimization of SNP selection and analysis of LD and
haplotypes, a pilot study is underway to produce a dense set of
genotypes across large genomic regions. Ten 500-kilobase regions of
the genome (see Supplementary Information, part 3) will besequenced in 48 unrelated HapMap DNA samples (16 CEPH
(currently being sequenced), 16 Yoruba, 8 Japanese and 8 Han
Chinese). All SNPs identified, as well any additional SNPs in the
public databases, will be genotyped in all of the 270 HapMap DNA
NATURE | VOL 426 | 18/25 DECEMBER 2003 | www.nature.com/naturesamples, and the genotype data will be released following theguidelines described above. This study will provide dense genotype
data for developing methods for SNP selection and for assessing thecompleteness of the information extracted, to guide the later stagesof genotyping.
When the HapMap is used to examine large genomic regions,the problem of multiple comparisons will arise from testing tens
to hundreds of thousands of SNPs and haplotypes for diseaseassociations. This will lead to difficulty in separating true fromfalse-positive results. Thus, new statistical methods, replication
studies and functional analyses of variants will be important toconfirm the findings and identify the functionally important
SNPs.

Conclusion
The goal of the International HapMap Project is to develop a
research tool that will help investigators across the globe to discover
the genetic factors that contribute to susceptibility to disease, toprotection against illness and to drug response. The HapMap will
provide an important shortcut to carry out candidate-gene, linkagebased and genome-wide association studies, transforming an unfeasible strategy into a practical one. In its scope and potential
consequences, the International HapMap Project has much incommon with the Human Genome Project, which sequenced thehuman genome63. Both projects have been scientifically ambitious
and technologically demanding, have involved intense international
collaboration, have been dedicated to the rapid release of data into
the public domain, and promise to have profound implications forour understanding of human biology and human health. Whereas
the sequencing project covered the entire genome, including the
99.9% of the genome where we are all the same, the HapMap will
characterize the common patterns within the 0.1% where we differ
from each other.
For the full potential of the HapMap to be realized, several things
must occur. The technology for genotyping must become more cost
efficient, and the analysis methods must be improved. Pilot studies
with other populations must be completed to confirm that the
HapMap is generally applicable, with consideration given to
expanding the HapMap if needed so that all major world populations can derive the greatest benefit. To use the tools created by
the HapMap, later projects must establish carefully phenotyped
sets of affected and unaffected individuals for many common
diseases in a way that preserves confidentiality but retains detailed
clinical and environmental exposure data. Longitudinal cohort
studies of hundreds of thousands of individuals will also be
invaluable for assessing the genetic and environmental contributions to disease.
Careful and sustained attention must also be paid to the ethicalissues that will be raised by the HapMap and the studies that will use
it. By consulting members of donor populations about the consent
process and the implications of population-specific findings before
sample collection, the project has helped to advance the ethicalstandard for international population genetics research. Future
population genetics projects will continue to refine this approach.
It will be an ongoing challenge to avoid misinterpretations or
misuses of results from studies that use the HapMap. Researchers
using the HapMap should present their findings in ways that avoid
stigmatizing groups, conveying an impression of genetic determinism, or attaching incorrect levels of biological significance to largelysocial constructs such as race.
The HapMap holds much promise as a powerful new tool for
discovery—to enhance our understanding of the hereditary factors
involved in health and disease. Realizing its full benefits will involvethe close partnership of basic science researchers, population
geneticists, epidemiologists, clinicians, social scientists, ethicists
and the public.
A© 2003 Nature Publishing Group793

feature
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Supplementary Information accompanies the paper on www.nature.com/nature.
Acknowledgements We thank many people who contributed to this project: J. Beck,
C. Beiswanger, D. Coppock, J. Mintzer and L. Toji at the Coriell Institute for Medical Research fortransforming the samples, distributing the DNA and cell lines, and storing the samples for use in
future research; J. Greenberg and R. Anderson of the NIH National Institute of General Medical
Sciences (NIGMS) for providing funding and support for cell-line transformation and storage in
the NIGMS Human Genetic Cell Repository at the Coriell Institute; K. Wakui at Shinshu
University for assistance in transforming the Japanese cell lines; N. Carter and D. Willey at the
Wellcome Trust Sanger Institute for flow sorting the chromosomes and for library construction,
respectively; M. Deschesnes and B. Godard for assistance at the University of Montréal;
C. Darmond-Zwaig, J. Olivier and S. Roumy at McGill University and Génome Québec
Innovation Centre; C. Allred, B. Gillman, E. Kloss and M. Rieder for help in implementing data
flow protocols; S. Olson for work on the website explanations; S. Adeniyi-Jones, D. Burgess,W. Burke, T. Citrin, A. Clark, D. Cowhig, P. Epps, K. Hofman, A. Holt, E. Juengst, B. Keats, J. Levin,
R. Myers, A. Obuoforibo, F. Romero, C. Tamura and A. Williamson for providing advice on the
project to NIH; A. Peck and J. Witonsky of the National Human Genome Research Institute(NHGRI) for help with project management; E. DeHaut-Combs and S. Saylor of NHGRI for staff
support; M. Gray for organizing phone calls and meetings; the people of Tokyo, Japan, the Yoruba
people of Ibadan, Nigeria, and the community at Beijing Normal University, who participated inpublic consultations and community engagements; and the people in these communities who
were generous in donating their blood samples. This work was supported in part by Genome
Canada, Génome Québec, the Chinese Ministry of Science and Technology, the Chinese Academyof Sciences, the Natural Science Foundation of China, the Hong Kong Innovation and Technology
Commission, the University Grants Committee of Hong Kong, the Japanese Ministry of
Education, Culture, Sports, Science and Technology, the Wellcome Trust, the SNP Consortium,
the US National Institutes of Health (FIC, NCI, NCRR, NEI, NHGRI, NIA, NIAAA, NIAID,NIAMS, NIBIB, NIDA, NIDCD, NIDCR, NIDDK, NIEHS, NIGMS, NIMH, NINDS, OD), theW.M. Keck Foundation and the Delores Dore Eccles Foundation.
Competing interests statement The authors declare that they have no competing financial
interests.
Correspondence and requests for materials should be addressed to D.B. (drb@sanger.ac.uk) or
M.F. (fost1848@msmailhub.oulan.ou.edu).

© 2003 Nature Publishing Group

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The International HapMap Consortium (Participants are arrangedalphabetically by institution, and then by principal investigator andalphabetically by last name.)
Genotyping centres: Baylor College of Medicine and ParAllele
BioScience Richard A. Gibbs1, John W. Belmont1, Paul Hardenbol2,
Thomas D. Willis2 & Fuli Yu1; Chinese HapMap Consortium
Huanming Yang3, Lan-Yang Ch’ang4, Wei Huang5, Bin Liu3, Yan Shen6,
Paul Kwong-Hang Tam7, Lap-Chee Tsui8, Mary Miu Yee Waye9,
Jeffrey Tze-Fei Wong10, Changqing Zeng3 & Qingrun Zhang3;
Illumina Mark S. Chee11, Luana M. Galver11, Semyon Kruglyak11,
Sarah S. Murray11 & Arnold R. Oliphant11; McGill University and GénomeQuébec Innovation Centre Alexandre Montpetit12, Thomas J. Hudson12,
Fanny Chagnon12, Vincent Ferretti12, Martin Leboeuf12, Michael S. Phillips12& Andrei Verner12; University of California at San Francisco andWashington University Pui-Yan Kwok13, Shenghui Duan14, Denise L. Lind13,
Raymond D. Miller14, John P. Rice14, Nancy L. Saccone14,
Patricia Taillon-Miller14 & Ming Xiao13; University of Tokyo and RIKEN
Yusuke Nakamura15,16, Akihiro Sekine16, Koki Sorimachi16,
Toshihiro Tanaka16, Yoichi Tanaka16, Tatsuhiko Tsunoda16 & Eiji Yoshino17;
Wellcome Trust Sanger Institute David R. Bentley18, Panos Deloukas18,
Sarah Hunt18 & Don Powell18; Whitehead Institute/MIT Center for
Genome Research David Altshuler19,20 & Stacey B. Gabriel19
Community engagement/public consultation and sample-collectiongroups: Beijing Normal University and Beijing Genomics InstituteHoucan Zhang21 & Changqing Zeng3; Health Sciences University of
Hokkaido, Eubios Ethics Institute and Shinshu University
Ichiro Matsuda22, Yoshimitsu Fukushima23, Darryl R. Macer24 & Eiko Suda24;
Howard University and University of Ibadan Charles N. Rotimi25,
Clement A. Adebamowo26, Toyin Aniagwu26, Patricia A. Marshall27,
Olayemi Matthew26, Chibuzor Nkwodimmah26 & Charmaine D. M. Royal25;
University of Utah Mark F. Leppert28 & Missy Dixon28
Analysis Groups: Cold Spring Harbor Laboratory Lincoln D. Stein29,
Fiona Cunningham29, Ardavan Kanani29 & Gudmundur A. Thorisson29;
Johns Hopkins University School of Medicine Aravinda Chakravarti30,
Peter E. Chen30, David J. Cutler30 & Carl S. Kashuk30; University of
Oxford Peter Donnelly31, Jonathan Marchini31, Gilean A. T. McVean31& Simon R. Myers31; University of Oxford, Wellcome Trust Centre for
Human Genetics Lon R. Cardon32, Gonçalo R. Abecasis33, Andrew Morris32& Bruce S. Weir34; US National Institutes of Health James C. Mullikin35,
Stephen T. Sherry36 & Michael Feolo36; Whitehead Institute/MIT Center
for Genome Research David Altshuler19,20, Mark J. Daly19& Stephen F. Schaffner19

Ethical, Legal and Social Issues: Chinese Academy of Social
Sciences Renzong Qiu37; Genetic Interest Group Alastair Kent38;
Howard University Georgia M. Dunston25; Kyoto University Kazuto Kato39;
Nagasaki University Norio Niikawa40; University of Montréal
Bartha M. Knoppers41; University of Oklahoma Morris W. Foster42;
Vanderbilt University Ellen Wright Clayton43 & Vivian Ota Wang43;
Wellcome Trust Jessica Watkin44
SNP Discovery: Baylor College of Medicine Richard A. Gibbs1,
John W. Belmont1, Erica Sodergren1 & George M. Weinstock1; Washington
University Richard K. Wilson45 & Lucinda L. Fulton45; Wellcome Trust
Sanger Institute Jane Rogers18; Whitehead Institute/MIT Center for
Genome Research Bruce W. Birren46
Scientific Management: Chinese Academy of Sciences Hua Han47;
Chinese Ministry of Science and Technology Hongguang Wang48;
Genome Canada Martin Godbout49 & John C. Wallenburg50;
Génome Québec Paul L’Archevêque51 & Guy Bellemare51; Japanese
Ministry of Education, Culture, Sports, Science and Technology
Kazuo Todani52, Takashi Fujita53 & Satoshi Tanaka52; The SNP Consortium
Arthur L. Holden54 & Eric H. Lai55; US National Institutes of HealthFrancis S. Collins56, Lisa D. Brooks56, Jean E. McEwen56, Mark S. Guyer56,
Elke Jordan57, Jane L. Peterson56, Jack Spiegel58, Lawrence M. Sung59& Lynn F. Zacharia56; Wellcome Trust Karen Kennedy44, Michael G. Dunn44,
Richard Seabrook44, Mark Shillito60, Barbara Skene44 & John G. Stewart44
Initial Planning Groups: Populations and Ethical, Legal and Social
Issues Group David L. Valle (chair)61, Ellen Wright Clayton (co-chair)43,
Lynn B. Jorde (co-chair)28, John W. Belmont1, Aravinda Chakravarti30,
Mildred K. Cho62, Troy Duster63,64, Morris W. Foster42, Marla Jasperse65,
Bartha M. Knoppers41, Pui-Yan Kwok13, Julio Licinio66, Jeffrey C. Long67,
Patricia A. Marshall27, Pilar N. Ossorio68, Vivian Ota Wang43,
Charles N. Rotimi25, Charmaine D. M. Royal25, Patricia Spallone44,69& Sharon F. Terry70; Methods Group Eric S. Lander (chair)46,
Eric H. Lai (co-chair)55, Deborah A. Nickerson (co-chair)71,
Gonçalo R. Abecasis33, David Altshuler19,20, David R. Bentley18,
Michael Boehnke33, Lon R. Cardon32, Mark J. Daly19, Panos Deloukas18,
Julie A. Douglas67, Stacey B. Gabriel19, Richard R. Hudson72,
Thomas J. Hudson12, Leonid Kruglyak73, Pui-Yan Kwok13,
Yusuke Nakamura15,16, Robert L. Nussbaum74, Charmaine D. M. Royal25,
Stephen F. Schaffner19, Stephen T. Sherry36, Lincoln D. Stein29& Toshihiro Tanaka16

Affiliations for participants: 1, Baylor College of Medicine Human Genome Sequencing Center, Department of Molecular and Human Genetics,
1 Baylor Plaza, Houston, Texas 77030, USA; 2, ParAllele BioScience, 384 Oyster Point Boulevard, Suite 8, South San Francisco, California 94080,
USA; 3, Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 100300, China; 4, Institute of Biomedical Sciences, 128 Yen-Jiou Yuan Road,
Sec. 2, Taipei, Taiwan, 115; 5, Chinese National Human Genome Center at Shanghai, 250 Bi Bo Road, Shanghai 201203, China; 6, Chinese National
Human Genome Center at Beijing, Yongchang North Road 3-707, Beijing Economy and Technology Development Zone, 100176, China; 7, Universityof Hong Kong, Genome Research Centre, 6/F, Laboratory Block, 21 Sassoon Road, Pokfulam, Hong Kong; 8, University of Hong Kong, 10/F, Knowles
Building, Pokfulam Road, Hong Kong; 9, The Chinese University of Hong Kong, Department of Biochemistry, Room 608, 6/F Mong Man Wai
Building, Shatin, Hong Kong; 10, Hong Kong University of Science and Technology, Department of Biochemistry, Clear Water Bay, Knowloon,
Hong Kong; 11, Illumina, 9885 Towne Centre Drive, San Diego, California 92121, USA; 12, McGill University and Génome Québec Innovation
Centre, 740 Dr Penfield Avenue, Montréal, Québec H3A 1A4, Canada; 13, University of California, San Francisco, Cardiovascular Research Institute,
505 Parnassus Avenue Long 1332A, Box 0130, San Francisco, California 94143, USA; 14, Washington University School of Medicine, 660 South Euclid
Avenue, St Louis, Missouri 63110, USA; 15, University of Tokyo, Institute of Medical Science, 4-6-1 Sirokanedai, Minato-ku, Tokyo 108-8639, Japan;
16, RIKEN SNP Research Center, 1-7-22 Suehiro-cho, Tsurumi-ku Yokohama, Kanagawa 230-0045, Japan; 17, RIKEN Technology Transfer andResearch Coordination Division, 2-1 Hirosawa, Wako, Saitama, Japan; 18, Wellcome Trust Sanger Institute, The Wellcome Trust Genome Campus,
Hinxton, Cambridge CB10 1SA, UK; 19, Whitehead Institute/MIT Center for Genome Research, 1 Kendall Square, Cambridge, Massachusetts 02139,
USA; 20, Massachusetts General Hospital, 50 Blossom Street, Wellman 831, Boston, Massachusetts 02114, USA; 21, Beijing Normal University,
19 Xinjiekouwai Street, Beijing 100875, China; 22, Health Sciences University of Hokkaido, Ezuko Institution for Developmental Disabilities,
Ezumachi 575, Kumamoto, Japan; 23, Shinshu University School of Medicine, Department of Medical Genetics, Matsumoto 390-8621, Japan;
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feature
24, University of Tsukuba, Eubios Ethics Institute, P.O. Box 125, Tsukuba Science City 305-8691, Japan; 25, Howard University, National Human
Genome Center, 2216 6th Street NW, Washington, District of Columbia 20059, USA; 26, University of Ibadan College of Medicine, Ibadan, Oyo State,
Nigeria; 27, Case Western Reserve University School of Medicine, Department of Bioethics, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA;28, University of Utah, Eccles Institute of Human Genetics, Department of Human Genetics, 15 North 2030 East, Salt Lake City, Utah 84112, USA;
29, Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA; 30, Johns Hopkins University School of Medicine,
McKusick–Nathans Institute of Genetic Medicine, 600 North Wolfe Street, Baltimore, Maryland 21287, USA; 31, University of Oxford, Department of
Statistics, 1 South Parks Road, Oxford OX1 3TG, UK; 32, University of Oxford, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford
OX3 7BN, UK; 33, University of Michigan, Department of Biostatistics, Center for Statistical Genetics, 1420 Washington Heights, Ann Arbor,
Michigan 48109, USA; 34, North Carolina State University, Bioinformatics Research Center, Campus Box 7566, Raleigh, North Carolina 27695,
USA; 35, US National Institutes of Health, National Human Genome Research Institute, 50 South Drive, Bethesda, Maryland 20892, USA
36, US National Institutes of Health, National Library of Medicine, National Center for Biotechnology Information, 8600 Rockville Pike, Bethesda,
Maryland 20894, USA; 37, Chinese Academy of Social Sciences, Center for Applied Ethics, 2121, Building 9, Caoqiao Xinyuan 3 Qu, Beijing 100054,
China; 38, Genetic Interest Group, 4D Leroy House, 436 Essex Road, London N1 3QP, UK; 39, Kyoto University, Institute for Research in Humanities,
Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan; 40, Nagasaki University Graduate School of Biomedical Sciences, Department of Human
Genetics, Sakamoto 1-12-4, Nagasaki 852-8523, Japan; 41, University of Montréal, The Public Law Research Centre (CRDP), P.O. Box 6128,
Downtown Station, Montréal, Québec H3C 3J7, Canada; 42, University of Oklahoma, Department of Anthropology, 455 West Lindsey Street,
Norman, Oklahoma 73019, USA; 43, Vanderbilt University, Center for Genetics and Health Policy, 507 Light Hall, Nashville, Tennessee 37232, USA;
44, Wellcome Trust, 183 Euston Road, London NW1 2BE, UK; 45, Washington University School of Medicine, Genome Sequencing Center, Box 8501,
4444 Forest Park Avenue, St Louis, Missouri 63108, USA; 46, Whitehead Institute/MIT Center for Genome Research, 9 Cambridge Center,
Cambridge, Massachusetts 02142, USA; 47, Chinese Academy of Sciences, 52 Sanlihe Road, Beijing 100864, China; 48, Chinese Ministry of Scienceand Technology, 15B Fuxing Road, Beijing 100862, China; 49, Genome Canada, 150 Metcalfe Street, Suite 2100, Ottawa, Ontario K2P 1P1, Canada;
50, McGill University, Office of Technology Transfer, 3550 University Street, Montréal, Québec H3A 2A7, Canada; 51, Génome Québec, 630 Boulevard
René-Lévesque Ouest, Montréal, Québec H3B 1S6, Canada; 52, Ministry of Education, Culture, Sports, Science and Technology, 3-2-2 Kasumigaseki,
Chiyodaku, Tokyo, Japan; 53, Hiraki and Associates, Toranomon No. 5 Mori Building, 17-1, Toranomon 1-Chome, Minato-Ku, Tokyo 105-0001,
Japan; 54, The SNP Consortium, 3 Parkway North, Deerfield, Illinois 60015, USA; 55, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park,
North Carolina 27709, USA; 56, US National Institutes of Health, National Human Genome Research Institute, 31 Center Drive, Bethesda,
Maryland 20892, USA; 57, Foundation for the National Institutes of Health, 1 Cloister Court, Bethesda, Maryland 20892, USA; 58, US National
Institutes of Health, Office of Technology Transfer, 6011 Executive Boulevard, Rockville, Maryland 20852, USA; 59, University of Maryland School ofLaw, 500 West Baltimore Street, Baltimore, Maryland 21201, USA; 60, Herbert Smith, Exchange House, Primrose Street, London EC2A 2HS, UK
61, Johns Hopkins University School of Medicine, Howard Hughes Medical Institute and the McKusick–Nathans Institute of Genetic Medicine,
725 North Wolfe Street, Baltimore, Maryland 21205, USA; 62, Stanford Center for Biomedical Ethics, 701AWelch Road, Palo Alto, California 94304,
USA; 63, New York University, Department of Sociology, 269 Mercer Street, New York, New York 10003, USA; 64, University of California, Berkeley,Department of Sociology, 2420 Bowditch, Berkeley, California 94720, USA; 65, University of New Mexico Health Sciences Center, 214 East Nizhoni
Boulevard, Gallup, New Mexico 87301, USA; 66, University of California, Los Angeles, School of Medicine, 695 Charles E. Young Drive South,
Los Angeles, California 90095, USA; 67, University of Michigan, Department of Human Genetics, 1241 East Catherine Street, Ann Arbor, Michigan
48109, USA; 68, University of Wisconsin School of Law, 975 Bascom Mall, Madison, Wisconsin 53706, USA; 69, The London School of Economics andPolitical Science, Houghton Street, London WC2A 2AE, UK; 70, Genetic Alliance, 4301 Connecticut Avenue NW, Suite 404, Washington, District ofColumbia 20008, USA; 71, University of Washington, Department of Genome Sciences, Box 357730, Seattle, Washington 98125, USA; 72, Universityof Chicago, Department of Ecology and Evolution, 1101 East 57th Street, Chicago, Illinois 60637, USA; 73, Fred Hutchinson Cancer Research Center,
1100 Fairview Avenue North, Seattle, Washington 98109, USA; 74, US National Institutes of Health, National Human Genome Research Institute,
49 Convent Drive, Bethesda, Maryland 20892, USA

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