利用X染色体失活特异性差异甲基化CpG位点检测特纳综合征：一项初步研究。

Detection of Turner syndrome using X-chromosome inactivation specific differentially methylated CpG sites: A pilot study.

作者信息

Zhang Qiang, Guo Xiaohong, Tian Tian, Wang Teng, Li Qiaoli, Wang Lei, Liu Yun, Xing Qinghe, He Lin, Zhao Xinzhi

机构信息

Children Hospital of Fudan University, Shanghai, China; Shanghai Key Laboratory of Prevention and Intervention of Birth Defects, Shanghai, China; Shanghai Center for Women and Children's Health, China.

Children Hospital of Fudan University, Shanghai, China; Shanghai Key Laboratory of Prevention and Intervention of Birth Defects, Shanghai, China.

出版信息

Clin Chim Acta. 2017 May;468:174-179. doi: 10.1016/j.cca.2017.03.008. Epub 2017 Mar 8.

DOI:10.1016/j.cca.2017.03.008

PMID:28284085

Abstract

BACKGROUND

Early diagnosis of Turner syndrome (TS) may improve preventive measures and treatment. X-chromosome inactivation specific differentially methylated CpG sites (XIDMSs) that are high methylated in inactive X chromosomes (Xi) and unmethylated in active X chromosomes (Xa) may be potential makers for TS detection.

METHODS

The candidate XIDMSs were screened from 9 male and 12 female DNA samples with normal karyotypes using the Illumina 450k array and validated by bisulfite sequencing PCR and pyrosequencing assay. X chromosome dosage was calculated according to the methylation level of multiple XIDMSs.

RESULTS

Overall, 108 candidate XIDMSs were screened by the 450k array. Validations indicated that XIDMSs gathered and formed the X-chromosome inactivation specific differentially methylated regions (XIDMRs). Using 3 XIDMRs at SAT1, UXT and UTP14A loci, 36 TS, 22 normal female and 6 male samples were analyzed. Methylation levels of the 20 XIDMSs in the XIDMRs could distinguish between TS and normal female DNA samples, the X chromosome dosage was consistent with karyotyping data. Analyzing samples of 2 triple X syndrome and 3 Klinefelter syndrome patients suggested that this method could be used to detect X chromosome aneuploids other than TS.

CONCLUSIONS

XIDMSs are widely spread along the X chromosome and might be effective markers for detection of TS and other X chromosome aneuploids.

摘要

背景

特纳综合征（TS）的早期诊断可能会改善预防措施和治疗效果。X染色体失活特异性差异甲基化CpG位点（XIDMSs）在失活的X染色体（Xi）中高度甲基化，而在活跃的X染色体（Xa）中未甲基化，可能是TS检测的潜在标志物。

方法

使用Illumina 450k芯片从9例核型正常的男性和12例核型正常的女性DNA样本中筛选候选XIDMSs，并通过亚硫酸氢盐测序PCR和焦磷酸测序分析进行验证。根据多个XIDMSs的甲基化水平计算X染色体剂量。

结果

总体而言，通过450k芯片筛选出108个候选XIDMSs。验证表明，XIDMSs聚集并形成了X染色体失活特异性差异甲基化区域（XIDMRs）。使用位于SAT1、UXT和UTP14A基因座的3个XIDMRs，对36例TS、22例正常女性和6例男性样本进行了分析。XIDMRs中20个XIDMSs的甲基化水平可以区分TS和正常女性DNA样本，X染色体剂量与核型分析数据一致。对2例XXX综合征和3例克氏综合征患者的样本分析表明，该方法可用于检测除TS以外的X染色体非整倍体。