Identification and pedigree analysis of ABO subgroup B303 / 中华医学遗传学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To explore the molecular mechanism of a case of ABO discrepancies based on the results of blood group serology.</p><p><b>METHODS</b>Five cases of the two-generation pedigrees were analyzed. ABO genotypes were determined using serological tests. DNA sequence analysis was performed on exon 6, exon 7 and intron 3 of the 5 cases to confirm the genotypes of a proband with B subgroup and 4 family members.</p><p><b>RESULTS</b>There were 3 cases of subgroup AB3 and 1 case of subgroup B3 among the 5 family members. The genotypes were identified as A102/B303 and O02/B303, respectively. B303 differed from B101 by intron 3 point mutation (intron3 + 5G>A).</p><p><b>CONCLUSION</b>The point mutation of intron 3 (intron 3+5G>A) is specific in B303.</p>