311份脐血样本HLA基因型无法判读原因探讨

Investigation of Uninterpretative HLA Typing in 311 Umbilical Cord Blood Samples

本研究探讨影响脐血样本HLA分型结果的因素。采用序列特异性引物PCR反应(sequence-specific prim-ing,SSP)对311份经过PCR-SSO和PCR-SSP方法仍无法判读HLA型别的脐血进行HLA低分辨重新分型,并对其中7份仍然无法确定HLA型别的脐血样本进行直接测序(sequence-based typing,SBT),分析无法判读的原因。结果显示:311份脐血样本中99.4%样本不能判定是因为当时HLA分型方法本身的限制性所造成的,0.6%样本不能判定的原因怀疑是脐血中存在母血污染所致。结论:HLA基因分型方法中序列特异性寡核苷酸探针杂交法(sequence-specific oligonucleotide probe hybridization,SSO)探针设计不足及PCR-SSP等位基因特异性引物的缺乏是影响HLA分型结果无法判读的主要因素。

The aim of this study was to investigate the factors which affect HLA typing in 311 umbilical cord blood （UCB） samples. The HLA low resolution typing of UCB samples with uninterpretative HLA types from 311 UCB samples analyzed by PCR-SSO and PCR-SSP was perfermed. 7 samples difficult to determine their HLA genotype were sequenced directly and the reason leading to uninterpretate HLA typing was analyzed. The results indicated that 99.4% of uninterpretative samples resulted from the restriction of HLA typing method itself and 0. 6% of uninterpretative samples were suspected to be contaminated with maternal blood in UCB. It is concluded that HLA typing is mainly affected by the shortcomings of oligonucleotide probe design for PCR-SSO and lack of allele specific primers of PCR- SSP.