双等位基因杂合性碱基缺失致类孟买血型一例  

Para-Bombay phenotype due to bi-allelic heterozygous base deletions of FUT1 gene

作　　者：何子毅[1] 胡应明[1] 许先国[2] 吴远军 崔四平[1] He Ziyi;Hu Yingming;Xu Xianguo;Wu Yuanjun;Cui Siping(Blood Transfusion Laboratory,Dongguan Blood Center,Dongguan,Guangdong 523000,China;Blood Transfusion Institute of Zhejiang Province,Hangzhou,Zhejiang 310052,China;Department of Blood Transfusion,Dongguan Maternal and Child Health Care Hospital,Dongguan,Guangdong 523000,China)

机构地区：[1]东莞市中心血站输血研究室,广东523000 [2]浙江省血液中心输血研究所,杭州310052 [3]东莞市妇幼保健院输血科,广东523000

出　　处：《中华医学遗传学杂志》2022年第11期1290-1293,共4页Chinese Journal of Medical Genetics

摘　　要：目的研究1例类孟买型血型的分子遗传机制。方法用血型血清学方法鉴定该献血者红细胞ABO和Lewis血型抗原表型,用PCR扩增类孟买表型个体的ABO基因第6、7外显子和FUT1基因全编码区,对PCR产物直接测序分析,并对FUT1基因的2处变异位点进行单倍体序列分析。结果血型血清学鉴定先证者为罕见的B型类孟买表型。直接测序发现先证者ABO基因为B.01/O.01.02杂合子;FUT1基因第881~882位和768位存在杂合性碱基缺失,进一步的单倍体分析显示其中1条单倍体存在c.881_882delTT,另1条单倍体存在c.768delC,基因型为FUT1*01N.13/01N.20杂合子,2个等位基因分别导致多肽链p.Phe294Cysfs*40和p.Val257Phefs*23移码变异。结论在献血人群中发现1例罕见的双等位基因复合杂合性碱基缺失导致的类孟买表型,其分子机制为c.881_882delTT和c.768delC所致的α-1,2岩藻糖基转移酶活性减弱。Objective To explore the genetic mechanism underlying a case with para-Bombay phenotype.Methods The ABO and Lewis phenotypes were identified with serological methods.The coding regions of exons 6 and 7 of the ABO and FUT1 genes were amplified with PCR and directly sequenced.Haploid sequence analysis was carried out on the variant sites of the FUT1 gene.Results Serological analysis confirmed that the proband has a rare para-Bombay phenotype.Direct sequencing revealed that he was a B.01/O.01.02 heterozygote for the ABO gene,and had heterozygous deletion for the 768 and 881-882 sites of the FUT1 gene.Further haploid analysis showed that the c.881_882delTT deletion has occurred in one haploid while c.768delC was present in the other haploid.The proband was therefore determined as a FUT1*01N.13/01N.20 heterozygote,which have resulted in frameshifts in polypeptide chain p.Phe294Cysfs*40 and p.Val257Phefs*23,respectively.Conclusion A rare bi-allelic heterozygous deletion of para-Bombay phenotype has been identified in a blood donor.The c.881_882delTT and c.768delC deletions may decrease the activity ofα-1,2-fucosyltransferase.

关 键 词：类孟买型 α-1 2岩藻糖基转移酶 FUT1基因 H血型系统 

分 类 号：R440[医药卫生—诊断学]