Drozda E A, Dean J D
Transfusion. 1985 May-Jun;25(3):280-1. doi: 10.1046/j.1537-2995.1985.25385219916.x.
The red cells of a patient typed as group O, but her serum lacked anti-A. Upon further testing, it appeared that the ABO phenotype was Am. Saliva studies demonstrated a normal amount of H substance but reduced A substance. Family studies established the ABO genotype of the proposita as A1O. The results suggest that modification of the cellular and salivary expression of the A antigen in this patient was the result of a double dose of the modifier gene y, and that the ABO phenotype, while having characteristics similar to that of an Am, was actually Ay.
一名患者的红细胞被鉴定为O型，但她的血清中缺乏抗A抗体。进一步检测发现，其ABO血型表型为Am型。唾液研究显示H物质含量正常，但A物质减少。家系研究确定先证者的ABO基因型为A1O。结果表明，该患者A抗原在细胞和唾液中的表达改变是由于修饰基因y的双剂量效应所致，且其ABO血型表型虽然具有与Am型相似的特征，但实际上是Ay型。
