Chen H, Lowther W, Avramopoulos D, Antonarakis S E
Center for Medical Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287-3914.
Hum Mutat. 1994;4(3):208-11. doi: 10.1002/humu.1380040306.
We report the isolation and characterization of a polymorphic pentanucleotide repeat (TAAAA)n, which was mapped to human chromosomes X and Y (loci DXYS156X and DXYS156Y) by PCR amplification of DNA from a monochromosomal somatic cell hybrid panel (NIGMS panel 2). The (TAAAA)n repeat of loci DXYS156 occurs within a human LINE element at a position where the consensus sequence contains a single TAAAA motif. In 72 unrelated CEPH individuals seven alleles were detected which ranged in size from 125 to 165 bp in 5 bp intervals. The two largest alleles (160 and 165 bp) were observed only in males, which suggests that they were amplified from the Y chromosome DXYS156Y locus. The other 5 alleles were present in two copies in females and in a single copy in males, which suggests that they were amplified from the X chromosome DXYS156X locus. Locus DXYS156X was polymorphic in CEPH families with an observed heterozygosity in females of 46% (27 of 59). Linkage analysis with DNA markers on the X chromosome revealed significant lod scores for a location of DXYS156X close to markers DXS1002 (theta = 0.000; zeta = 8.43), DXYS1X (theta = 0.015; zeta = 17.3), DXS3, and PGK1 in the region of chromosome Xq13. The sequence of DXYS156Y derived from the 165 bp allele has been deposited in Genbank with accession number X71600.
我们报告了一种多态性五核苷酸重复序列（TAAAA）n的分离和特性分析，通过对来自单染色体体细胞杂交板（NIGMS板2）的DNA进行PCR扩增，将其定位到人类X和Y染色体上（基因座DXYS156X和DXYS156Y）。DXYS156基因座的（TAAAA）n重复序列出现在人类LINE元件内，该位置的共有序列包含一个单一的TAAAA基序。在72名无关的CEPH个体中，检测到7个等位基因，大小范围为125至165 bp，间隔为5 bp。仅在男性中观察到两个最大的等位基因（160和165 bp），这表明它们是从Y染色体DXYS156Y基因座扩增而来的。其他5个等位基因在女性中以两个拷贝存在，在男性中以一个拷贝存在，这表明它们是从X染色体DXYS156X基因座扩增而来的。DXYS156X基因座在CEPH家族中具有多态性，女性的观察杂合度为46%（59人中的27人）。与X染色体上的DNA标记进行连锁分析，结果显示DXYS156X靠近标记DXS1002（θ = 0.000；ζ = 8.43）、DXYS1X（θ = 0.015；ζ = 17.3）、DXS3和PGK1位于Xq13染色体区域，其lod分数显著。来自165 bp等位基因的DXYS156Y序列已存入Genbank，登录号为X71600。
