脆性 X 综合征携带者筛查在产前诊断中的实施：单中心的初步研究。

Implementation of fragile X syndrome carrier screening during prenatal diagnosis: A pilot study at a single center.

机构信息

Department of Medical Genetics & the Prenatal Diagnosis Center of Hunan Province, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan, China.

NHC Key Laboratory of Birth Defects for Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan, China.

出版信息

Mol Genet Genomic Med. 2021 Jul;9(7):e1711. doi: 10.1002/mgg3.1711. Epub 2021 May 31.

DOI:10.1002/mgg3.1711

PMID:34057320

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8372084/

Abstract

BACKGROUND

Fragile X syndrome (FXS) is the most common inherited form of intellectual disability. Prenatal screening of FXS allows for early identification and intervention. The present study explored the feasibility of FXS carrier screening during prenatal diagnosis for those who were not offered screening early in pregnancy or prior to conception.

METHODS

Pregnant women to be offered amniotic fluid testing were recruited for the free voluntary carrier screening at a single center between August, 2017 and September, 2019. The number of CGG repeats in the 5' un-translated region of the fragile X mental retardation gene 1 (FMR1) was determined.

RESULTS

4286 of 7000 (61.2%) pregnant women volunteered for the screening. Forty (0.93%), five (0.11%), and three (0.07%) carriers for intermediate mutation (45-54 repeats), premutation (55-200 repeats) and full mutation (>200 repeats) of the FMR1 gene were identified respectively. None of the detected premutation alleles were inherited by the fetuses. Of the three full mutation carrier mothers, all had a family history and one transmitted a full mutation allele to her male fetus.

CONCLUSION

Implementation of FXS carrier screening during prenatal diagnosis may be considered for the need to increase screening for FXS.

摘要

背景

脆性 X 综合征（FXS）是最常见的遗传性智力障碍。FXS 的产前筛查可实现早期发现和早期干预。本研究旨在探讨对那些未在妊娠早期或妊娠前进行筛查的孕妇，在产前诊断中进行 FXS 携带者筛查的可行性。

方法

在 2017 年 8 月至 2019 年 9 月期间，在一家单中心招募了接受羊膜穿刺术的孕妇，以进行免费的自愿携带者筛查。脆性 X 智力低下基因 1（FMR1）5'非翻译区的 CGG 重复数被确定。

结果

7000 名孕妇中有 4286 名（61.2%）自愿参加了筛查。分别发现 40 名（0.93%）、5 名（0.11%）和 3 名（0.07%）孕妇为 FMR1 基因中间突变（45-54 次重复）、前突变（55-200 次重复）和全突变（>200 次重复）携带者。未发现检测到的前突变等位基因遗传给胎儿。在 3 名全突变携带者母亲中，均有家族史，1 名母亲将全突变等位基因传递给了她的男性胎儿。