论文部分内容阅读
本研究探索1例类孟买型血型的分子机制,为稀有血型的筛选和鉴定提供理论基础。以血型血清学方法鉴定该个体红细胞的ABO和H表型,利用聚合酶链反应扩增类孟买表型个体的abo基因第6、7外显子和α1,2岩藻糖基转移酶基因(fut1)编码区,并对PCR产物直接测序分析。对纯化的fut1扩增产物进行TOPO克隆和测序,对2处变异位点进行单倍体序列分析。结果表明:血清学分析确认该个体为罕见的类孟买表型;直接测序发现先证者fut1基因第547位和880位附近存在碱基缺失或插入变异;TOPO克隆测序法证实,fut1基因1条单倍体存在第547-552位两碱基AG缺失,另1条单倍体存在880-882位两碱基TT缺失。这2种变异均导致移码突变,并提前形成终止密码。结论:在献血人群中发现1例罕见的类孟买表型,其分子机制为双碱基缺失型fut1等位基因复合杂合所致的α1,2岩藻糖基转移酶活性减弱。
This study explored the molecular mechanism of a Mulatta-like blood group, providing a theoretical basis for the screening and identification of rare blood group. The ABO and H phenotypes of the individual erythrocytes were identified by serological method. The 6,7 and 7 exons of the abo gene and α1,2-fucosyltransferase gene were amplified by polymerase chain reaction fut1) coding region, and direct sequencing analysis of PCR products. TOPO cloning and sequencing of the purified fut1 amplification product were performed, and haplotype sequence analysis was performed on the two mutation sites. The results showed that the serotype was a rare Mulatta-like phenotype. The direct sequencing revealed that there was a base deletion or insertion mutation near the positions 547 and 880 of the fut1 gene of proband. TOPO cloning and sequencing confirmed that there was 1 fut1 gene Haploid 547-552 presence of two base AG deletion, the other a haplotype 880-882 two-base TT deletion. Both of these mutations lead to frameshift mutations and the formation of a stop codon in advance. CONCLUSION: A rare case of Mulatta-like phenotype was found in blood donors. Its molecular mechanism is that the α1,2-fucosyltransferase activity induced by the complex hybrid of the two-base deletion type fut1 allele is weakened.