Kutsche R, Brown C J
Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada.
Genomics. 2000 Apr 1;65(1):9-15. doi: 10.1006/geno.2000.6153.
The large number of redundant sequences available in nucleotide databases provides a resource for the identification of polymorphisms. Expressed polymorphisms in X-linked genes can be used to determine the inactivation status of the genes, and polymorphisms in genes that are subject to inactivation can then be used as tools to examine X-chromosome inactivation status in heterozygous females. In this study, we have identified six new X-linked single-nucleotide polymorphisms and determined the inactivation status of these genes by examination of expression patterns in female cells previously demonstrated to have skewed inactivation, as well as by analysis of somatic cell hybrids retaining the inactive human X chromosome. Expression was seen from both alleles in females heterozygous for the RPS4X gene, confirming the previously reported expression from the inactive X chromosome. Expression of only a single allele was seen in females heterozygous for polymorphisms in the BGN, TM4SF2, ATP6S1, VBP1, and PDHA1 genes, suggesting that these genes are subject to X-chromosome inactivation.
核苷酸数据库中大量的冗余序列为多态性的鉴定提供了资源。X连锁基因中表达的多态性可用于确定基因的失活状态，而那些会发生失活的基因中的多态性随后可作为工具来检测杂合女性中的X染色体失活状态。在本研究中，我们鉴定出六个新的X连锁单核苷酸多态性，并通过检测先前证明具有偏态失活的女性细胞中的表达模式，以及分析保留失活人类X染色体的体细胞杂种，来确定这些基因的失活状态。在RPS4X基因杂合的女性中，两个等位基因均有表达，这证实了先前报道的来自失活X染色体的表达。在BGN、TM4SF2、ATP6S1、VBP1和PDHA1基因多态性杂合的女性中，仅观察到一个等位基因的表达，这表明这些基因会发生X染色体失活。
