Genetic Indentification of An Individual with A102Bw33 Blood Group Gene Subtypes of ABO Variant

Abstract

To investigate and indentify the molecular characteristics of a sample serologically identified as ABw subgroup. The individual was confirmed by standard serological techniques. The genotyping and sequencing were performed using polymerase chain reaction-sequence specific primer (PCR-SSP), direct sequencing and gene cloning for exon 6 and exon 7 of ABO locus respectively. Both A and B antigen were detected on red blood cells of the proband and anti-B antibody was detected in his serum. PCR-SSP showed that the sample gene was A1B phemotype. DNA sequencing showed 297A/G, 467C/T, 526C/G, 657C/T, 703A/G, 803G/C and 930G/A heterozygote in exon 6 to exon 7. After cloning and sequencing, 2 alleles A102 and Bw33 were obtained. The sequence of Bw33 allele had one nucleotide change (A to C) at position 796 compared with that of B101 allele. The nucleotide in this B allele at site 796 is a "C" characteristic of the A form of the allele. A>C at nt796 of α-1, 3 galactosyltransferase gene can result in Bw33 phenotype with the anti-B antibody in serum.