Published online 13 November 2011 Nucleic Acids Research, 2012, Vol. 40, Database issue D1023–D1029 doi:10.1093/nar/gkr958 BGMUT: NCBI dbRBC database of allelic variations of genes encoding antigens of blood group systems Santosh Kumar Patnaik1, Wolfgang Helmberg2 and Olga O. Blumenfeld3,* 1Department of Thoracic Surgery, Roswell Park Cancer Institute, Buffalo, NY 14203, USA, 2Department of Blood Group Serology and Transfusion Medicine, Medical University of Graz, Graz A-8036, Austria and 3Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA Received August 15, 2011; Revised September 27, 2011; Accepted October 13, 2011 ABSTRACT Analogous to human leukocyte antigens, blood group antigens are surface markers on the erythro- cyte cell membrane whose structures differ among individuals and which can be serologically identified. The Blood Group Antigen Gene Mutation Database (BGMUT) is an online repository of allelic variations in genes that determine the antigens of various human blood group systems. The database is manually curated with allelic information collated from scientific literature and from direct submis- sions from research laboratories. Currently, the database documents sequence variations of a total of 1251 alleles of all 40 gene loci that together are known to affect antigens of 30 human blood group systems. When available, information on the geo- graphic or ethnic prevalence of an allele is also provided. The BGMUT website also has general in- formation on the human blood group systems and the genes responsible for them. BGMUT is a part of the dbRBC resource of the National Center for Biotechnology Information, USA, and is available online at http://www.ncbi.nlm.nih.gov/projects/gv/ rbc/xslcgi.fcgi?cmd=bgmut. The database should be of use to members of the transfusion medicine community, those interested in studies of genetic variation and related topics such as human migra- tions, and students as well as members of the general public. INTRODUCTION The BGMUT Blood Group Antigen Gene Mutation Database documents variations in genes that encode antigens for human blood groups. It is a part of the dbRBC resource (1) of the National Center for Biotechnology Information (NCBI) of USA and can be freely accessed online at http://www.ncbi.nlm.nih.gov/ projects/gv/rbc/xslcgi.fcgi?cmd=bgmut. Recent documentation of the extent and the surprisingly high numbers of mutations in the human genome have suggested that, perhaps with the exception of identi- cal twins, no two individuals bear exact copies of chromosomal DNA. In those studies, DNA of random subjects is compared but more often phenotypic differ- ences observed in disease states, whether single gene in- herited disorders or in association studies of complex conditions are taken as criteria for selection of individuals whose DNA is examined for sequence changes. In the latter studies, large fragments of DNA are usually examined and compared statistically to matched control individuals. Changes in blood group phenotypes are another criterion for selection of subjects who may show differences in sequences of two or more deﬁned sets of genes. These genes encode a group of red cell membrane proteins that are polymorphic in the population and are deﬁned as blood group antigens; in addition, these genes may encode certain glycosyltransferases that are involved in the synthesis of red cell membrane glycans whose struc- tures also differ among individuals. The former group consists of structural molecules, channels, adhesion molecules or enzymes and, excluding their red cell membrane location, can be considered as representative of any human protein, whereas the latter are similar to most other glycosyltransferases. Evidence suggests that sequence changes in these proteins or even their absence, such as in phenotypes, is not, in most cases, physio- logically harmful. The proteins or the glycans fulﬁll their role as blood group antigens because they are polymorphic in the popu- lation and their sequence changes can be readily predicted by serological approaches; they are known as ‘antigens’ because in the course of transfusion, or pregnancy, the presence of a variant protein epitope is recognized as ‘non-self’ and may ultimately result in an adverse *To whom correspondence should be addressed. Tel: +1 718 430 2814; Fax: +1 718 430 8565; Email: olga.blumenfeld@einstein.yu.edu The Author(s) 2011. Published by Oxford University Press. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/3.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.