Allele and Genotype Frequencies of the ABO Blood Group System in a Palestinian Population

Abstract

The ABO blood group antigens are of clinical importance in blood transfusion, organ transplantation, autoimmune hemolytic anemia and fetomaternal blood group incompatibility. The ABO locus are located on chromosome 9. Till now, more than 200 ABO alleles have been identified by molecular investigations. The objective of this study was to determine the major ABO alleles' and genotypes' frequencies in a Palestinian population residing in Gaza Strip. A four separate–reaction multiplex allele specific polymerase chain reaction (AS-PCR) was used to determine the ABO genotypes. Our study population consisted of 201 unrelated subjects (50 males and 151 females) whose DNA extracted from peripheral blood was subjected to genotyping. The genotypes of 201 samples were found to be A1A1 (n=3), A1O 1(n=24), A1O2 (n=25), A1A2 (n=4), A2A2 (n=2), A2O1 (n=13), A2O2 (n=2), B1B1 (n=5), B1O1 (n=26), B1O2 (n=14), A1B (n=11), A2B (n=4) , O1O1 (n=31) , O1O2 (n=26) and O2O2 (n=11), from which the deduced phenotypes were A (n=73), B (n=45), AB (n=15) and O (n=68).Moreover, there was no significant difference between observed and expected genotypes and the genotyping results were consistent with Hardy-Weinberg law. The frequencies of A1 , A2 , B1, O1 and O2 alleles were: 0. 174, 0.067, 0.162, 0.376 and 0.221 respectively. The rare cis-ABO1 allele was not encountered in the study population. The genotype results were compared with serologically determined phenotypes and there were no deviation. To our knowledge, this is the first study inGaza strip investigating the ABO genotypes. ABO genotyping has practical applications in blood transfusion, tissue/organ transplantation, blood typing discrepancies and forensic/paternity testing investigations.