Genes Genet. Syst. (2000) 75, p. 141–147

Evolution of the ABO blood group genein Japanese macaque
Reiko Noda 1,2, Takashi Kitano1,4, Osamu Takenaka3, and Naruya Saitou1, 2, *1

Laboratory of Evolutionary Genetics, National Institute of Genetics, Mishima 411-8540, Japan2
Department of Genetics, School of Life Science, The Graduate University for Advanced
Studies, Mishima 411-8540, Japan
3
Primate Research Institute, Kyoto University, Inuyama 484-8506, Japan
4
Present address: Max-Planck Institute of Molecular Anthropology,
Leipzig, Germany(Received 18 December, 1999, accepted 31 May 2000)

We determined 5 sequences of Japanese macaque ABO blood group gene exon 7(ca. 0.5kb) and 2 sequences for exon 5 and intron 6 (ca. 1.7kb). We compared thosedata with published sequences of other Old World monkey species, and the results
suggest that alleles A and B were polymorphic in the ancestral species of macaques,
and that B type allele evolved independently in macaque and baboon lineages.

INTRODUCTION
The human ABO blood group was discovered byLandsteiner, and its mode of inheritance as multiple alleles at a single genetic locus was established by Bernstein(see Crow [1993] for review). Immunodominant ABH
antigens are carbohydrate structures of glycoproteins andglycolipids (see Yamamoto [1995] for review). ABO alleles A and B thus code for glycosyltransferases which transfer GalNAc and galactose, respectively, while O is a nullallele incapable of coding for a functional glycosyltransferase. Yamamoto et al. (1990) determined the cDNA
sequences of three common alleles, A1, B, and O, andYamamoto et al. (1995) determined the genomic organization of the gene.
Existence of A-like and B-like antigens in non-humanprimates were known (reviewed in Blancher and Socha[1997]). Serological typing of variety of primate species
revealed the presence of an A-like antigen in common
chimpanzee (Pan troglodytes: 90% of the typed individuals), bonobo or pygmy chimpanzee (Pan paniscus: 100%),
gibbon (Hylobates: 19%), orangutan (Pongo pygmaeus:56%), and most Old World monkey species (0–100%) as
well as some New World monkey species (22–100%).
Similarly, a B-like antigen was detected in all the gorillasubspecies (Gorilla gorilla gorilla, G. g. graueri, G. g.
beringei: 100%), gibbon (42%), and virtually all Old World
monkey species (0–100%) as well as some New World monkey species (27–100%; see Blancher and Socha [1997] forreview). These serological typing data suggested that
A-like and B-like antigens arose early in evolution of priEdited by Naoyuki Takahata* Corresponding author. E-mail: nsaitou@genes.nig.ac.jp

mates, possibly before the divergence of the Platyrrhini
and Catarrhini. This may be called “trans-specific polymorphism” hypothesis, and was first proposed by Bernard
and Ruffié (1972).
Kominato et al. (1992) determined the ABO group geneexon 7 sequences of chimpanzee, gorilla, orangutan, crabeating macaque, and yellow baboon. Martinko et al.
(1993) supported the trans-species polymorphism hypothesis in hominoids based on their sequence data. Saitou
and Yamamoto (1997) analyzed sequence data of the ABO
blood group gene exon 7 that determines the activity of
the glycosyltransferase-encoding genes from the human,
chimpanzee, gorilla, orangutan, and some Old World
monkeys. They proposed that the common ancestralgene for the hominoid and Old World monkey ABO bloodgroup gene was A type, and that B alleles evolved independently in human, gorilla, and baboon lineages.
O’hUigin et al. (1997) determined the ABO blood groupgene partial sequences between exon 5 and exon 7 of human, chimpanzee, and gorilla. They also suggested thatthe B allele evolved independently in human and gorilla.
Diamand et al. (1997) determined the A, B, and O allele
nucleotide sequences of olive baboon. Doxiadis et al.
(1998) determined sequences of human, rhesus macaque,and crab-eating macaque for ABO blood group genes exon
7 and they showed that all O type alleles so far found inprimates were considered to be inactivated A genes, andthat A and B reactivity was generated independently
in the hominoid and Old World monkey lineages.
Kermarrec et al. (1999) determined sequences of O typealleles for two rhesus macaque and one chimpanzee.
They also suggested that A and B reactivities were generated independently in hominoid and Old World monkey
lineages, and that O alleles are species-specific, resulting

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from independent silencing mutations. Those observations reinforce the hypothesis that the polymorphism inprimates reflects convergent evolution rather thantranspecies inheritance of ancestral alleles.
Japanese macaque is phylogenetically closely related
species of crab-eating macaque and rhesus macaque (e.g.,
Hayasaka et al., 1996), and there is only B type in Japanese macaque (Blancher and Socha, 1997). The purposeof this paper is to determine and to analyze the sequenceof Japanese macaque ABO blood group genes. Evolutionof ABO blood group gene in Old World monkey will be discussed based on the novel sequence data.
MATERIALS AND METHOD
The genomic DNA samples for five Japanese macaque(Macaca fuscata) individuals collected by one of us (O.T.)
were used.
PCR was carried out using specific primers based onhuman and chimpanzee exon 7, and based on chimpanzeeand gibbon exon 6. Primers are: SN-10, an exon 7 downTable 1.

stream specific primer, 5'-CGATGCCGTTGGCCTGGTC3', SN-02, an exon 7 upstream specific primer, 5'-GAGACGGCGGAGAAGCACTT-3', and SN-15, an exon 6 specificprimer, 5'-AGCAGTTCAGGCTCCAGAACAC3'.
Each PCR reaction mixture contained 160mM each ofdATP, dTTP, dCTP and dGTP, 150µM MgCl2, 1 × reaction
buffer containing no Mg2+ ion, 1mM of each primer, and 2
unit Taq polymerase (TOYOBO and NIPPON GENE).
About 200ng of genomic DNA was used as template. The
PCR program consisted of 20–45 cycles of 1-min denaturation at 94°C followed by 1-min primer annealing at 65°C
or 68°C and 2-min extension at 72°C. Immediately
preceding and following these 20–45 cycles, a 9-min hotstart step at 94°C and 60-min extension step at 72°C were
included, respectively. We used GeneAmp PCR system
2400 and 9700 (PE Biosystems).
PCR products were confirmed by 1.5% agarose gel
eletctrophoresis, and purified using Micro Spin Columns(Pharmacia Biotech). The purified PCR products weresequenced by the dideoxy chain-termination method using fluorescent ddNTPs, sequenase enzyme and buffer

Nucleotide sequences of the Old World monkey ABO blood group genes used in this study

Sequence
nameAlleletype

Length(bp)

Reference

Accession
numberJapanese macaque
JaM-B1JaM-B2
JaM-B3
JaM-B4
JaM-B5

B
B
B
B
B

487
487
487
1734a
1678b

This study (sample ID #011)
This study (sample ID #012)
This study (sample ID #013)
This study (sample ID #014)
This study (sample ID #015)

AB041525
AB041526
AB041527
AB041528
AB041529

Crab eating macaque
CeM-A1
CeM-O
CeM-A2
CeM-A3
CeM-B1
CeM-B2

A
O
A
A
B
B

571
559
471
571
571
571

Macaque of Kominato et al. (1992)
Cy*O101 of Doxiadis et al. (1998)
Cy*A102 of Doxiadis et al. (1998)
Cy*A103 of Doxiadis et al. (1998)
Cy*B101 of Doxiadis et al. (1998)
Cy*B102 of Doxiadis et al. (1998)–
AF052081
AF052078
AF052079
AF052082
AF052083

Rhesus macaque
RhM-A1
RhM-B1
RhM-B2
RhM-B3RhM-O1
RhM-O2c
RhM-O2c

A
B
B
B
O
O
O

571
571
571
571
700
700
868

Rh*A101 of Doxiadis et al. (1998)
Rh*B101 of Doxiadis et al. (1998)
Rh*B102 of Doxiadis et al. (1998)
Rh*B103 of Doxiadis et al. (1998)
Rh*O of Kermarrec et al. (1999)
MamuO of Doxiadis et al. (1998)
Rh*O*01 of Kermarrec et al. (1999)

AF052080
AF052084
AF052085
AF052086
AF094695
AF094693
AF071830

Yellow baboon
YeB-A
YeB-B

A
B

571
571

Baboon-1 of Kominato et al. (1992)
Baboon-2 of Kominato et al. (1992)––

Olive baboon
O1B-A
O1B-B
O1B-O

A
B
O

690
690
690

Baboon A of Diamand et al.(1997)
Baboon B of Diamand et al.(1997)
Baboon O of Diamand et al.(1997)

AF019416
AF019417
AF019418a

1211bp intron 6 is included.
1156bp intron 6 is included.
c
Doxiadis et al. (1998) and Kermarrec et al. (1999) reported rhesus macaque O allele sequences, butthey are identical for the overlapped region. Therefore they were considered as one allele.
bEvolution of Japanese macaque ABO genes
from ThermoSequenase Kit (PE Biosystems).
Samples were electrophoresed using the ABI PRISM
377 sequencer (PE Biosystems). All the three PCR primers were used for sequencing. In addition, two otherprimers were used. They are: SN-04, an exon 7 upstream,
5'-ACGTCCTGCCAGCGCTTGTA-3', and SN-14, an intron
6, 5'-CCACCAGCACCCCCTCTTACT-3'.
CLASTAL W ver.1.6 (Thompson et al., 1994) was used
for multiple alignment and phylogenetic tree construction.
Phylogenetic trees were constructed by using the neighbor-joining method (Saitou and Nei, 1987). Phylogenetic
networks (Bandelt, 1994; Saitou and Yamamoto, 1997)
were also constructed.
RESULTS AND DISCUSSION
PCR amplification using primer combinations SN-10/
SN-02 was conducted for Japanese macaque genomic DNA
as template, and yielded about 0.5kb fragments. We firstcompared those five sequences with the 17 publishedsequence data of rhesus macaque, crab-eating macaque,and olive baboon (Kominato et al., 1992; Diamand et al.,Table 2.

1997; Doxiadis et al., 1998; Kermarrec et al., 1999).
Sequences used in this study are listed in Table 1, andvariant nucleotide sites are shown in Table 2. There was
no gap in the multiple aligned sequences. We did not findany heterozygotes in 487bp region of exon 7 for 5 individuals nor in the 1.0kb region intron 6 for 2 individuals. The
nucleotide diversity within Japanese macaque is 1.59% in
mtDNA (Hayasaka et al. 1996), and the average heterozygosity estimated from protein polymorphism was 2.8%
(Nozawa et al. 1996). This low diversity of Japanesemacaque is compatible with our result.
We first constructed a phylogenetic tree for these 22
exon 7 sequences (Fig. 1). Most of branch lengths arevery short, and bootstrap values are small. This tree isessentially unrooted, but we located the putative root in
the branch separating A alleles and B alleles.
There are two hypotheses which can explain the sharing of blood group A and B antigens among primates.
The first hypothesis posits that the sharing is the resultof polymorphism being carried over from ancestral todescendent species in the course of primate evolution (thetrans-species polymorphism hypothesis). The second

Variant sites of ABO blood group gene in Old World monkeys
intron 6

143

exon 7Site
number13688 837622 795417 01 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11
2 2 2 3 3 3 3 3 3 3 4 4 4 5 5 5 5 5 5 6 6 6 6 6 6 7 77
6 8 9 0 1 1 1 2 4 5 4 7 9 2 3 5 5 9 9 2 4 5 6 7 9 0 36
7 5 7 0 7 8 9 7 2 7 0 6 8 8 1 1 8 3 7 7 3 0 0 0 2 8 02

Consensus*******ＧＣＣＣＣＧＧＧＧＧＣＣＧＣＣＣＧＣＧＡＣＧＣＧＣＧ *JaM_B1
JaM_B2
JaM_B3
JaM_B4
JaM_B5
CeM_A1
CeM_O
CeM_A2
CeM_A3
CeM_B1
CeM_B2
RhM_A1
RhM_O1
RhM_O2
RhM_B1
RhM_B2
RhM_B3
YeB_A
YeB_B
OIB_A
OIB_B
OIB_O

******************ＣＡＴＣＣＡＴＧＣＴＧＧ******************************************************************************************************

ＣＴＴ・・・・・・・・・・・・・・・・・・・・・Ａ・・*
Ｃ・ＧＴ・・・・・・・・・・・・・・・・・・・・・・・*
Ｃ・・・・・・・・・・・・・・・・Ａ・・・・・・・・・*
Ｔ・Ｇ・・・・・・・・・・・・・・・・・・・・・・・・*
Ｔ・・・・・・・・・・・・・・・・Ａ・・・・・・・・・**・・・Ｔ・・・・・ＡＴＴＡＧ・Ｔ・・・ＴＧ・・・・・** *・・・Ｔ・・・・・ＴＴ・・・Ｔ・・・ＴＧ・・・・・Ｃ*・・・・Ｔ・・・ＡＡＴＴＡＧ・Ｔ・・・ＴＧ・・・・・**・・・・Ｔ・・ＡＡＡＴＴ・・・Ｔ・・・ＴＧ・・・・・Ｃ*・・・・・Ａ・・・・・・・・・・・・Ａ・・・・・・・Ｔ*・・・・・・・・・・・・・・・・・・・・・・Ａ・・ＡＴ*・・・・Ｔ・・・・・ＴＴＡＧ・・・・・ＴＧ・・・Ａ・Ｃ*・・・・Ｔ・・・・ＡＴＴＡＧ・Ｔ・・・ＴＧ・・・・・Ｃ*・・・・・・・・・・・・・・・・・・・・・・・・・ＡＴ*・・・・・・・・・・・・・・・・・Ｔ・・・・・・・ＡＴ*・・Ａ・・・・・・・・・・・・・・・・・・・・・・ＡＴ*・・・・・・・・・・・・・・・・・Ｔ・・・・・・・・Ｔ*Ｃ・・Ｔ・・・・・・・・ＡＧ・・・・・ＴＧＡ・・・・ **Ｃ・・Ｔ・・・・・・・・ＡＧ・Ｔ・・・・・・・・・・ **Ｃ・・・Ｔ・・・・・・・ＡＧ・・・・・ＴＧＡ・・・・Ｃ*Ｃ・・・Ｔ・・・・・・・ＡＧ・・・・・・・・・・・・Ｃ*Ｃ・・・Ｔ・Ａ・・・ＴＴＡＧＧＴ・・・ＴＧＡ・・・・Ｃ

Notes. The variant sites in intron 6 to exon 7 are shown. Dots and asterisks
denote identical nucleotides with the consence and nonexamined positions,
respectively. In this region, there are no gaps within Old World monkey
sequences. Sites 1643 and 1650 are the critecal sites between A and B
allele. All Japanese macaque sequences have the same nucleotides as otherprimate B type alleles in these two critical setes.

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Fig. 1. The phylogenetic tree of the ABO blood group gene exon 7 in Old World monkeys. This tree is rooted in the branch between Atype and B-type sequences. Bootstrap values only greater than 50% are shown.

Fig. 2. The phylogenetic network of the ABO blood group gene in Old World monkeys. The numbers on edges show site numbers. The
thick-lined edges are the two critical sites between A and B alleles. Nodes with open circles, full circles, and squares denote A type, B
type, and O type alleles, respectively. A curved broken line denotes connection between macaque B type alleles and others (nosubstitution). Substitutions that were thought to occurred parallel is shown with asterisk.

Evolution of Japanese macaque ABO genes
invokes parallel evolution as an explanation for the interspecific sharing of antigenic determinants. The former
hypothesis was supported by Martinko et al. (1993); thelatter was proposed by Saitou and Yamamoto (1997) andis more consistent with partial intron 6 hominoid sequence
data described by O’hUigin et al. (1997). In Old World
monkey, we should consider these two hypotheses. In
Fig. 1, the bootstrap value for the branch between A allele
and B allele group is 46%. We therefore can’t determine
which hypothesis is correct. The bootstrap value for the
branch between macaques B alleles and other alleles ishigh, 97%. Therefore, the polymorphism of A and B alleles seems to be maintained at least before the speciationof three macaques.
We then constructed the phylogenetic network of those
ABO exon 7 sequences for three macaque species and two
baboon species (Fig. 2). Sequence data between site 1297
and site 1730 were used. Numbers on edges show site
numbers, and the thick-lined branches denote the two
critical sites between A and B alleles. Sequences shownwith open circles are A type alleles, and those shown withfull circles are B type. All O type alleles shown with open
squares are located within the A type allele variations except for one O type allele (RhM-O2), which is within the B
type group. There are many incompatibilities, and theresulting network is complex. All the incompatibilities
are presented in the form of reticulation in this network
except for site 1558. The sequences YeB-B, OlB-O, CeMO, RhM-O1, CeM-A2, and CeM-A3 share the same nucleotide T at this site (other sequences are C). But YeB-B isseparated from other 1558-T group sequences with morethan 8 substitutions, so we inferred that the substitutions
from C to T in 1558 occurred twice in the YeB-B lineage
and in the lineage leading to OlB-O, CeM-O, RhM-O1,
CeM-A2, and CeM-A3, designated with asterisks.

Fig. 3.

145

In this network, the B type alleles of macaque and RhMO2 formed a clear cluster, as in the NJ tree in Fig. 1 (thebootstrap value is 97%), and the topology within the B typealleles are similar to that of the NJ tree. The CeM-A2,
RhM-O1, and CeM-O share the same nucleotide at site
1558, and their distances are small (one or two substitutions), but CeM-O is located outside of the cluster that contains CeM-A2, RhM-O1, CeM-A3, OlB-O, and RhM-A1 in
the NJ tree, and the distance between CeM-O and RhMO1/CeM-A2 in the NJ tree is bigger than that of the
network. This discrepancy between the tree and the network may be caused from incompatibilities among sites
1357–1440, sites 1528–1531, and site 1558.
Based on the the phylogenetic network shown in Fig. 2,
the B type alleles of three macaques (Japanese macaque,rhesus macaque, and crab-eating macaque) are closely related to each other, compared to the A type alleles ofrhesus and crab-eating macaques. It is thus clearlyshown that the A and B polymorphism arose before thespeciation of these macaques. The nucleotide differences
between A type and B type alleles in macaque are large(at least 4 including the critical sites), while baboon alleles are located within the macaque variation. There isone baboon specific site at 1285, and the nucleotide is C inbaboons, while it is T or G in macaques (see Table 2).
Furthermore in intron 6, there are some species specificsites for baboon and macaque (Noda et al., unpublisheddata). These suggest that baboon alleles constitute amonophyletic group.
From the network and these informations, we chose onetree (Fig. 3). This tree has two major differences fromthat of Fig. 1. First one is the location of baboon sequences. The baboon sequences are monophyletic in Fig.
3, while they are scattered and are not monophyletic in
the tree of Fig. 1, especially OlB-O is separated from otherA possible rooted tree of the Old World monkey ABO blood group gene based on the phylogenetic network of Fig. 2.

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R. NODA et al.

baboon sequences. The second one is the location of
A-like sequences. For example, RhM-A1 and CeM-A3 arelocated outside of the other A-like sequences in Fig. 3, butthey locate inside of the A-like sequence cluster in Fig. 1.
In Fig. 4, we show the hypotheses on the evolutionary
history of the ABO blood group gene in macaque andbaboon. Fist two figures show the hypotheses which havealready been proposed; (A) convergent evolution (B typeallele evolved independently in each macaque and baboon
lineage after speciation) and (B) ancestral polymorphism.

Under the hypothesis (A), the parallel substitutions were
supposed to occur in two critical sites (shown as thick line)
in Fig. 2, and the parallel substitutions were supposed tooccurr in sites that are incompatible with critical sites(for example, site numbers 1357–1440 and 1528–1531)
under hypothesis (B). We must assume that parallelchanges occurred many times under both hypotheses.
Fig. 4 (C) shows our hypothesis that is a mixture of convergent evolution and ancestral polymorphism. This isbased on the tree of Fig. 3, and the number of substitu-

Fig. 4. Three hypotheses for evolution of ABO polymorphism in macaque and baboon lineages. (A) convergent evolution, (B) ancestralpolymorphism, and (C) the hypothesis based on the tree of Fig. 3. The dotted line shows the speciation of macaque and baboon.

Fig. 5.
man.

The phylogenetic tree of the ABO blood group gene intron 6 and exon 7 in Japanese macaque, chimpanzee, bonobo, and hu-

Evolution of Japanese macaque ABO genes
tions in this scheme is less than those of (A) and (B).
Thus, this tree looks most plausible.
We also aligned two Japanese macaque sequences
spanning exon 6 to exon 7 with chimpanzee and bonobo
sequences spanning intron 6 and partial exon 7 (Kitano etal., 2000) as well as human (Olsson and Chester, 1998),
and constructed a phylogenetic tree (Fig. 5). In this tree,
three genera (Homo, Pan, and Macaca) clearly make theirown clusters. The distance between hominoids andmacaque is substantial, thus the convergent evolution
hypothesis is more compatible with this tree. The
difference between chimpanzees and Japanese macaqueis around 16–17%. If this corresponds to 25–30 MY divergence between hominoid and Old World monkeys, coalescent of the two Japanese macaque sequences (0.5%) isestimated to be 0.7–0.9 MYA under the assumption ofmolecular clock. The nucleotide diversity of Japanesemacaque was estimated to be about 1.5% in the mitochondrial DNA, and the divergence times among Japanesemacaques were estimated to be 0.19–0.37 MYA (Hayasaka
et al., 1996). It should be noted that the effective population size of nuclear DNA is four times larger than that of
mitochondrial DNA. Observed difference of coalescenttimes between the ABO gene and mitochondrial DNA ismore or less compatible with this expected difference ofthe effective population size.
In conclusion, the type change between A and B allelesof the ABO blood group gene occurred independently atleast two times in Old World monkey, in the macaque/baboon ancestor and the baboon lineages.
We thank Dr. Kenta Sumiyama for various discussions in theearlier version. We also thank Dr. Antoine Blancher for
informing us the paper by Bernard and Ruffié (1972). This study
was partially supported by grants in aid for scientific studies from
Ministry of Education, Science, Sports and Culture, Japan to
NS.

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