新生儿ABO*A2.08亚型等位基因的鉴定及蛋白结构分析  

ABO*A2.08 Subtype Allele Identification and Protein Structure Analysis in Newborns

作　　者：刘昕[1] 王莲慧 舒锦[1] 徐子恒[1] 徐秀云[1] LIU Xin;WANG Lian-Hui;SHU Jin;XU Zi-Heng;XU Xiu-Yun(Department of Blood Transfusion,Jiangxi Provincial Children′s Hospital,Nanchang 330006,Jiangxi Province,China)

机构地区：[1]江西省儿童医院输血科,江西南昌330006

出　　处：《中国实验血液学杂志》2024年第1期225-230,共6页Journal of Experimental Hematology

基　　金：江西省卫生健康委科技计划(SKJP220201919)。

摘　　要：目的:研究ABO*A2.08亚型的血清学特征和蛋白结构,探究其遗传学分子机制。方法:利用血清学方法对先证者及其家系成员进行ABO血型鉴定,应用聚合酶链反应-序列特异性方法进行ABO基因分型,并对ABO基因第6、7外显子直接测序分析,通过同源蛋白保守性分析、3D分子建模和蛋白稳定性预测探究A2.08亚型中基因突变对GTA蛋白结构稳定性的影响。结果:先证者血清学结果为Ax亚型,ABO基因分型明确先证者的基因型为ABO*A207/08;先证者的父亲基因测序结果证实ABO基因第7外显子存在c.539G>C特征性变异,导致多肽链p.Arg180Pro(R180P)替换。3D蛋白分子建模与分析提示R180P突变后蛋白结构中局部氨基酸的氢键数目发生改变,蛋白稳定性预测显示该突变对蛋白结构稳定性影响较大。结论:ABO基因第7外显子c.539G>C突变导致多肽链氨基酸替换,影响了GTA蛋白结构的稳定性,引起酶活性改变,产生A2.08表型,且该变异基因可稳定遗传。Objective:To study the serological characteristics of ABO*A2.08 subtype and explore its genetic molecular mechanism.Methods:ABO blood group identification was performed on proband and her family members by routine serological methods.ABO genotyping and sequence analysis were performed by polymerase chain reaction-sequence specific primer(PCR-SSP),and direct sequencing of PCR products from exons 6 and 7 of ABO gene were directly sequenced and analyzed.The effect of gene mutation in A2.08 subtype on structural stability of GTA protein was investigated by homologous protein conserved analysis,3D molecular modeling and protein stability prediction.Results:The proband′s serological test results showed subtype Ax,and ABO genotyping confirmed that the proband′s genotype was ABO*A207/08.Gene sequencing of the proband′s father confirmed the characteristic variation of c.539G>C in the 7th exon of ABO gene,leading to the replacement of polypeptide chain p.Arg180Pro(R180P).3D protein molecular modeling and analysis suggested that the number of hydrogen bonds of local amino acids in the protein structure was changed after the mutation,and protein stability prediction showed that the mutation had a great influence on the protein structure stability.Conclusion:The mutation of the 7th exon c.539G>C of ABO gene leads to the substitution of polypeptide chain amino acid,which affects the structural stability of GTA protein and leads to the change of enzyme activity,resulting in the A2.08 phenotype.The mutated gene can be stably inherited.

关 键 词：ABO基因 基因分型 基因测序 3D分子模型 

分 类 号：R457.11[医药卫生—治疗学]