Akane A, Mizukami H, Shiono H
Department of Legal Medicine, Kansai Medical University, Moriguchi, Japan.
Vox Sang. 2000;79(3):183-7. doi: 10.1159/000031239.
We had classified the M alleles of the MN blood group system into two subtypes, M(G) (standard M) and M(T), based on a G/T substitution in intron 1 of the glycophorin A (GPA) gene. This study provides further study on nucleotide sequences of M(G), M(T) and N alleles to profile the new allele, M(T).
M(G), M(T) and N alleles of the GPA gene were amplified using GPA gene-specific primers to avoid co-amplification of the genes of glycophorins B and E. Then the 5'-flanking region, exons 1-7 and introns 1-4 of the alleles were analyzed by DNA sequencing.
There were 17 nucleotide substitutions and deletions between M(G) (standard M) and N alleles. Ten of the M(T) nucleotides were M(G)-type but the other 7 were N-type. M(T) allele also showed one base change and one deletion that were observed in neither the M(G) nor the N allele. Moreover, we found nucleotide substitutions within each allele, allowing further classification of the alleles.
By the sequence data of M(G), M(T) and N alleles, the three alleles could be further classified into M101 and M102, M201 and M202, and N101 and N102, respectively.
基于糖蛋白A（GPA）基因内含子1中的G/T替换，我们已将MN血型系统的M等位基因分为两个亚型，即M(G)（标准M）和M(T)。本研究进一步对M(G)、M(T)和N等位基因的核苷酸序列进行研究，以描绘新等位基因M(T)的特征。
使用GPA基因特异性引物扩增GPA基因的M(G)、M(T)和N等位基因，以避免糖蛋白B和E基因的共扩增。然后通过DNA测序分析等位基因的5'侧翼区、外显子1 - 7和内含子1 - 4。
M(G)（标准M）和N等位基因之间存在17个核苷酸替换和缺失。M(T)的10个核苷酸为M(G)型，但另外7个为N型。M(T)等位基因还显示出一个在M(G)和N等位基因中均未观察到的碱基变化和一个缺失。此外，我们在每个等位基因内发现了核苷酸替换，从而可以对等位基因进行进一步分类。
通过M(G)、M(T)和N等位基因的序列数据，这三个等位基因可进一步分别分为M101和M102、M201和M202以及N101和N102。
