Hm. Chen et al., HOMOLOGOUS LOCI DXYS156X AND DXYS156Y CONTAIN A POLYMORPHIC PENTANUCLEOTIDE REPEAT (TAAAA)(N) AND MAP TO HUMAN X-CHROMOSOME AND Y-CHROMOSOME, Human mutation, 4(3), 1994, pp. 208-211
We report the isolation and characterization of a polymorphic pentanuc
leotide repeat (TAAAA)(n), which was mapped to human chromosomes X and
Y (loci DXYS156X and DXYS156Y) by PCR amplification of DNA from a mon
ochromosomal somatic cell hybrid panel (NIGMS panel 2). The (TAAAA)(n)
repeat of loci DXYS156 occurs within a human LINE element at a positi
on where the consensus sequence contains a single TAAAA motif. In 72 u
nrelated CEPH individuals seven alleles were detected which ranged in
size from 125 to 165 bp in 5 bp intervals. The two largest alleles (16
0 and 165 bp) were observed only in males, which suggests that they we
re 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 observ
ed 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; z=8.43), D
XYS1X (theta=0.015; z=17.3), DXS3, and PGK1 in the region of chromosom
e Xq13. The sequence of DXYS156Y derived from the 165 bp allele has be
en deposited in Genbank with accession number X71600. (C) 1994 Wiley-L
iss, Inc.