Since our description of the molecular genetic basis of the three major alleles and several minor alleles, additional ABO alleles have been molecularly characterized and their sequence information has been deposited in the national database (http://www.ncbi.nlm.nih.gov/gv/mhc/xslcgi.cgi?cmd=bgmut/home), which was established by Professor Olga Blumenfeld at Albert Einstein College of Medicine. Olsson, Chester, and colleagues (Hansen et al., 1998; Olsson and Chester, 1995, 1996a, b, c, 1998, 2001; Olsson et al., 1997; Olsson et al., 2001; Olsson et al., 1998; Olsson et al., 1995), Blancher and colleagues (Kermarrec et al., 1999; Roubinet et al., 2002; Roubinet et al., 2001), Seltsam, Blasczyk, and colleagues (Seltsam et al., 2002; Seltsam et al., 2003), Ogasawara and colleagues (Ogasawara et al., 1996a; Ogasawara et al., 1998; Ogasawara et al., 2001; Ogasawara et al., 1996b), and Yip and colleagues (Yip, 2000, 2002; Yip et al., 1996; Yip et al., 1995) played an important role in this expansion. The total number of defined alleles currently stands at 178, and the full listing of alleles is shown above.  This table was prepared based on data culled from the dbRBC - Blood Group Antigen Gene Mutation Database. 

18. ABO Alleles (BGAGMD)

01. ABO Blood Group System

Blumenfeld, O. dbRBC - Blood Group Antigen Gene Mutation Database (http://www.ncbi.nlm.nih.gov/gv/mhc/xslcgi.cgi?cmd=bgmut/home)

Hansen, T., Namork, E., Olsson, M.L., Chester, M.A., and Heier, H.E. (1998). Different genotypes causing indiscernible patterns of A expression on A(el) red blood cells as visualized by scanning immunogold electron microscopy. Vox Sang 75, 47-51.

Kermarrec, N., Roubinet, F., Apoil, P.A., and Blancher, A. (1999). Comparison of allele O sequences of the human and non-human primate ABO system. Immunogenetics 49, 517-526.

Ogasawara, K., Bannai, M., Saitou, N., Yabe, R., Nakata, K., Takenaka, M., Fujisawa, K., Uchikawa, M., Ishikawa, Y., Juji, T., et al. (1996a). Extensive polymorphism of ABO blood group gene: three major lineages of the alleles for the common ABO phenotypes. Human Genet 97, 777-783.
Ogasawara, K., Yabe, R., Uchikawa, M., Bannai, M., Nakata, K., Takenaka, M., Takahashi, Y., Juji, T., and Tokunaga, K. (1998). Different alleles cause an imbalance in A2 and A2B phenotypes of the ABO blood group. Vox Sang 74, 242-247.
Ogasawara, K., Yabe, R., Uchikawa, M., Nakata, K., Watanabe, J., Takahashi, Y., and Tokunaga, K. (2001). Recombination and gene conversion-like events may contribute to ABO gene diversity causing various phenotypes. Immunogenetics 53, 190-199.
Ogasawara, K., Yabe, R., Uchikawa, M., Saitou, N., Bannai, M., Nakata, K., Takenaka, M., Fujisawa, K., Ishikawa, Y., Juji, T., et al. (1996b). Molecular genetic analysis of variant phenotypes of the ABO blood group system. Blood 88, 2732-2737.
Olsson, M.L., and Chester, M.A. (1995). A rapid and simple ABO genotype screening method using a novel B/O2 versus A/O2 discriminating nucleotide substitution at the ABO locus. Vox Sang 69, 242-247.
Olsson, M.L., and Chester, M.A. (1996a). Evidence for a new type of O allele at the ABO locus, due to a combination of the A2 nucleotide deletion and the Ael nucleotide insertion. Vox Sang 71, 113-117.
Olsson, M.L., and Chester, M.A. (1996b). Frequent occurrence of a variant O1 gene at the blood group ABO locus. Vox Sang 70, 26-30.
Olsson, M.L., and Chester, M.A. (1996c). Polymorphisms at the ABO locus in subgroup A individuals. Transfusion 36, 309-313.
Olsson, M.L., and Chester, M.A. (1998). Heterogeneity of the blood group Ax allele: genetic recombination of common alleles can result in the Ax phenotype. Transfus Med 8, 231-238.
Olsson, M.L., and Chester, M.A. (2001). Polymorphism and recombination events at the ABO locus: a major challenge for genomic ABO blood grouping strategies. Transfus Med 11, 295-313.
Olsson, M.L., Guerreiro, J.F., Zago, M.A., and Chester, M.A. (1997). Molecular analysis of the O alleles at the blood group ABO locus in populations of different ethnic origin reveals novel crossing-over events and point mutations. Biochem Biophys Res Commu 234, 779-782.
Olsson, M.L., Irshaid, N.M., Hosseini-Maaf, B., Hellberg, A., Moulds, M.K., Sareneva, H., and Chester, M.A. (2001). Genomic analysis of clinical samples with serologic ABO blood grouping discrepancies: identification of 15 novel A and B subgroup alleles. Blood 98, 1585-1593.
Olsson, M.L., Santos, S.E., Guerreiro, J.F., Zago, M.A., and Chester, M.A. (1998). Heterogeneity of the O alleles at the blood group ABO locus in Amerindians. Vox Sang 74, 46-50.
Olsson, M.L., Thuresson, B., and Chester, M.A. (1995). An Ael allele-specific nucleotide insertion at the blood group ABO locus and its detection using a sequence-specific polymerase chain reaction. Biochem Biophys Res Commun 216, 642-647.
Roubinet, F., Janvier, D., and Blancher, A. (2002). A novel cis AB allele derived from a B allele through a single point mutation. Transfusion 42, 239-246.
Roubinet, F., Kermarrec, N., Despiau, S., Apoil, P.A., Dugoujon, J.M., and Blancher, A. (2001). Molecular polymorphism of O alleles in five populations of different ethnic origins. Immunogenetics 53, 95-104.
Seltsam, A., Hallensleben, M., Eiz-Vesper, B., Lenhard, V., Heymann, G., and Blasczyk, R. (2002). A weak blood group A phenotype caused by a new mutation at the ABO locus. Transfusion 42, 294-301.
Seltsam, A., Hallensleben, M., Kollmann, A., Burkhart, J., and Blasczyk, R. (2003). Systematic analysis of the ABO gene diversity within exons 6 and 7 by PCR screening reveals new ABO alleles. Transfusion 43, 428-439.
Yip, S.P. (2000). Single-tube multiplex PCR-SSCP analysis distinguishes 7 common ABO alleles and readily identifies new alleles. Blood 95, 1487-1492.
Yip, S.P. (2002). Sequence variation at the human ABO locus. Annals Human Genet 66, 1-27.
Yip, S.P., Choy, W.L., Chan, C.W., and Choi, C.H. (1996). The absence of a B allele in acquired B blood group phenotype confirmed by a DNA based genotyping method. J Clin Pathol 49, 180-181.
Yip, S.P., Yow, C.M., and Lewis, W.H. (1995). DNA polymorphism at the ABO locus in the Chinese population of Hong Kong. Hum Hered 45, 266-271.