一条罕见重排Y染色体的结构分析及其与基因型-表型相关性的关系

Structural analysis of a rare rearranged Y chromosome and its bearing on genotype-phenotype correlation.

作者信息

Ogata T, Wakui K, Kosho T, Muroya K, Yamanouchi Y, Takano T, Fukushima Y, Rappold G, Suzuki Y

机构信息

Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.

出版信息

Am J Med Genet. 2000 Jun 5;92(4):256-9.

PMID:10842291

Abstract

We report on a 9-year-old boy with a rare rearranged Y chromosome and borderline short stature (-2.0 SD). Standard metaphase chromosome analysis indicated a 46,X,i(Y)(q1O) karyotype, but high resolution G-banding showed an asymmetric band pattern for the rearranged Y chromosome. FISH and DNA studies for a total of 15 different Y chromosomal loci or regions showed that the rearranged Y chromosome was accompanied by: 1) a partial deletion of the short arm pseudoautosomal region (PAR1) involving SHOX, with the breakpoint distal to DXYS85; and 2) a partial duplication of Yq, with the breakpoint proximal to DAZ. The karyotype was determined as 46,X,?i(Y)(q1O).ish der(Y)(Yqter--> Yp11.3::Yq11.2-->Yqter)(DAZ++,DYZ3+,SRY +, SHOX-). The X chromosome and the autosomes were normal. The results suggest that haploinsufficiency of SHOX is primarily responsible for the borderline short stature, and that the deletion of the PAR1 may result in spermatogenic failure due to defective X-Y pairing and recombination in the PAR1.

摘要

我们报告了一名9岁男孩，他有一条罕见的重排Y染色体且身材接近矮小（低于平均身高2.0标准差）。标准中期染色体分析显示其核型为46,X,i(Y)(q10)，但高分辨率G显带显示重排Y染色体的带型不对称。对总共15个不同的Y染色体位点或区域进行的荧光原位杂交（FISH）和DNA研究表明，重排Y染色体伴有：1）短臂假常染色体区域（PAR1）的部分缺失，涉及SHOX基因，断点位于DXYS85远端；2）Yq的部分重复，断点位于DAZ近端。核型确定为46,X,?i(Y)(q10)。ish der(Y)(Yqter→Yp11.3::Yq11.2→Yqter)(DAZ++,DYZ3+,SRY +, SHOX-)。X染色体和常染色体正常。结果表明，SHOX单倍体不足是导致身材接近矮小的主要原因，PAR1的缺失可能由于PAR1中X-Y配对和重组缺陷而导致生精障碍。