Mizukami Hajime, Akane Atsushi, Shiono Hiroshi, Ogawa Kento
Department of Legal Medicine, Asahikawa Medical College, Japan.
Leg Med (Tokyo). 2002 Mar;4(1):13-20. doi: 10.1016/s1344-6223(01)00057-8.
Highly-homologous Glycophorin A (GPA), B and E genes are triplicate genes, and involve many subtypes and minor antigens constructing the Miltenberger subsystem. These genes and most of the variants are hypothesized to arise by recombination, because hot spots are located in the gene sequences. By sequencing exons 1-7 and introns 1-3 of standard alleles of GPA gene, M and N alleles were classified into six variations: provisionally called MN*M101, M102, M201, M202, N101 and N102 in our previous study. Here we further investigated the sequences of introns 4-6 using GPA gene-specific primers and by DNA sequencing, and found eight, five and nine new nucleotide substitutions or deletions in introns 4, 5 and 6, respectively. Using the computer program PHYLIP 3.5, the phylogenetic trees were reconstructed. Phylogenetic analysis of the allele sequences revealed that M200s alleles arose from M101 after the separation of M101 and N101 and branched to M201 and M202 via the accumulation of point mutations. M102 and N102 alleles were estimated to generate via recombination between M101 and N101 occurred around the hot spot. The findings also suggested the existence of other GPA variants with normal antigenicity, and are quite useful in the forensic and anthropological fields.
高度同源的血型糖蛋白A（GPA）、B和E基因是三重基因，涉及构成米尔滕贝格系统的许多亚型和次要抗原。这些基因和大多数变体被推测是通过重组产生的，因为热点位于基因序列中。通过对GPA基因标准等位基因的外显子1-7和内含子1-3进行测序，M和N等位基因被分为六种变异：在我们之前的研究中暂称为MN*M101、M102、M201、M202、N101和N102。在这里，我们使用GPA基因特异性引物并通过DNA测序进一步研究了内含子4-6的序列，分别在内含子4、5和6中发现了8个、5个和9个新的核苷酸替换或缺失。使用计算机程序PHYLIP 3.5重建了系统发育树。对等位基因序列的系统发育分析表明，M200s等位基因在M101和N101分离后从M101产生，并通过点突变的积累分支到M201和M202。估计M102和N102等位基因是通过在热点附近发生的M101和N101之间的重组产生的。这些发现还表明存在其他具有正常抗原性的GPA变体，在法医和人类学领域非常有用。
