Genetic and bioinformatics analysis of an individual with Am phenotype due to variant of A-glycosyltransferase en-zyme gene
10.13303/j.cjbt.issn.1004-549x.2024.10.019
- VernacularTitle:A糖基转移酶基因变异导致Am表型的遗传学和生物信息学分析
- Author:
Xu ZHANG
1
;
Zhuren ZHOU
;
Xuying HUANG
;
Lichun LI
;
Xiaofeng LI
;
Jianping LI
Author Information
1. 沈阳中心血站/辽宁省血液中心输血医学研究所,辽宁沈阳 110044
- Keywords:
Am phenotype;
A-glycosyltransferase enzyme;
molecular-genetic;
bioinformatics analysis
- From:
Chinese Journal of Blood Transfusion
2024;37(10):1193-1196
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the serological characteristics and molecular mechanism of an individual with Am phenotype.Methods The sample with ABO blood group discrepancy was confirmed by serological techniques.The full cod-ing and flanking regions of the ABO gene including intron 1 transcription factor binding site were identified through direct se-quencing of PCR-amplified products.PCR products of exon 6-7 were validated to isolate the ABO gene haplotypes by clo-ning and sequencing individual colonies.Bioinformatics software was used to analyze the structure of the mutant protein.Re-sults The serologic characteristics of ABO blood typing showed the rare Am phenotype.The c.467C/T and c.912C/A heter-ozygous sites in exon 7 were identified by direct sequencing analysis.Further TA cloning and sequencing revealed that the patient carried an ABO*O.01.01 allele and a novel ABO*A allele.The new allele sequence had one nucleotide alteration(C＞A)at position 912 on the background of the ABO*A1.02 allele.The new allele sequence has been included in the Gen-Bank database with the entry number JX489776.The c.912C＞A mutation was predicted to be"probably damaging"and"deleterious"by PolyPhen2 and PROVEAN algorithms,respectively.The free energy change(ΔΔG)value predicted it to have a destabilizing effect on the GTA protein.Meanwhile,modeling of the 3D structure predicted that the p.S304R amino acid substitution may alter the hydrogen bond of the GTA protein.Conclusion The p.S304R substitution of α-1,3-N-acetylgalactosaminyltransferase gene may reduce the antigen expression owing to a greatly destabilizing effect on the structure and function of the GTA protein.
