ALLELIC DIVERSITY IS GENERATED BY INTRAEXON SEQUENCE EXCHANGE AT THE DRB1 LOCUS OF PRIMATES
ALLELIC DIVERSITY IS GENERATED BY INTRAEXON SEQUENCE EXCHANGE AT THE DRB1 LOCUS OF PRIMATES
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DOI：
10.1073/pnas.88.9.3686
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发表时间：
1991-05-01
影响因子：
11.1
通讯作者：
ERLICH, HA
中科院分区：
文献类型：
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作者：
GYLLENSTEN, UB;SUNDVALL, M;ERLICH, HA
编码II类细胞表面抗原HLA-DR、-DQ和-DP的基因座表现出显著程度的等位基因多态性。 大多数II类等位基因多样性定位于第二外显子，其编码β-折叠片层，随后是α-螺旋结构域。 在这里，系统发育分析的39个人类DRB 1等位基因和21 DRB 1等位基因获得的聚合酶链反应（PCR）扩增从一组密切相关的灵长类动物揭示，编码的β-折叠片和编码的α-螺旋的第二个域的序列具有不同的进化历史。 在β-折叠片的多态性已被保存在物种之间，似乎反映了单倍型之间的祖先的关系，而编码α-螺旋结构域的多态性片段似乎已被插入到不同的祖先DRB 1序列的框架内的等位基因间序列交换。 因此，DRB 1基因座的等位基因多态性可能部分是通过组合两个结构域的不同变体而产生的。
The loci encoding the class II cell surface antigens HLA-DR, -DQ, and -DP exhibit a remarkable degree of allelic polymorphism. Most of the class II allelic diversity is localized to the second exon, which encodes a beta-pleated sheet followed by an alpha-helical domain. Here, phylogenetic analysis of 39 human DRB1 alleles and 21 DRB1 alleles obtained by polymerase chain reaction (PCR) amplification from a set of closely related primates reveals that sequences encoding the beta-pleated sheet and those encoding the alpha-helix of the second domain have different evolutionary histories. The polymorphisms in the beta-pleated sheet have been conserved between species and appear to reflect the ancestral relationships among haplotypes, whereas polymorphic segments encoding the alpha-helical domain appear to have been inserted by interallelic sequence exchange into the framework of different ancestral DRB1 sequences. Allelic polymorphism at the DRB1 locus may thus have been generated in part by combining different variants of the two structural domains.