浙江汉族RHD 1227A等位基因的五个家系遗传研究

Investigation of RHD 1227A allele in five pedigrees in Zhejiang Han population

目的研究DEL表型、RHD1227A等位基因的家系遗传规律。方法用吸收放散的血清学方法鉴定Rh DEL表型,用特异于RHD1227A等位基因的聚合酶链反应-序列特异性引物扩增方法(polymerasechain reaction-sequence specific primer ,PCR-SSP)、RHD1227A等位基因第9外显子的序列分析方法和Rhesus hybrid box鉴定的方法来检测RHD1227A等位基因和RHD基因的杂合性。结果 5个DEL表型先证者都是RHD1227A等位基因阳性,同时缺失1个RHD等位基因,为RHD1227A/RHd杂合子;家系1、2、3的先证者都有一位亲代成员携带RHD1227A等位基因,同时还携带正常RHD等位基因,为RHD1227A/RHD杂合子,表现为正常D表型;家系1先证者子代遗传了RHD1227A基因,但是为RHD1227A/RHD杂合子,表现为正常D表型;家系2、4、5先证者的子代成员未遗传RHD1227A基因,为正常D表型。结论 RHD1227A等位基因是DEL表型的重要遗传标记,相对于正常RHD等位基因隐性,而相对于缺失的RHd基因显性;RHD1227A等位基因为亲代遗传基因,而非个体基因变异。

Objective To analysis the genetic mode of Rh DEL phenotype and RHD 1227A allele in Zhejiang Han population through family investigations. Methods Rh DEL phenotypes were identified by a serologic adsorptionelution method. Two polymerase chain reaction-sequence specific prime （PCR-SSP） methods which detectED RHD 1227A allele and Rhesus hybrid box, respectively, and a nucleotide sequencing method focused on the exon 9 of RHD 1227A allele were employed to determine the zygosity of RHD allele. Results All five probands with Rh DEL phenotype harbored a RHD 1227A allele and had a RHD allele deletion, and they were RHD 1227A/RHd heterozygote. One of the parent members was found to contain a RHD 1227A allele and a normal RHD allele in pedigree 1, 2 and 3, respectively. Thus, they were RHD 1227A/RHD heterozygotes and presented normal D positive phenotype. The son of proband No 1. inherited the RHD 1227A allele and presented a normal D positive phenotype due to a RHD 1227A/RHD heterozygote; The offsprings of proband No. 2, No. 4, and No. 5 did not inherit RHD 1227A allele and presented a normal D positive phenotype. Conclusion RHD 1227A allele is an important genetic marker of Rh DEL phenotype; RHD 1227A is recessive to normal RHD allele and dominant to RHd allele; RHD 1227A allele is an ancestral, but not a spontaneously mutated allele.