Case Report
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Nov 6, 2019; 7(21): 3655-3661
Published online Nov 6, 2019. doi: 10.12998/wjcc.v7.i21.3655
Compound heterozygous mutation of MUSK causing fetal akinesia deformation sequence syndrome: A case report
Na Li, Chong Qiao, Yuan Lv, Tian Yang, Hao Liu, Wen-Qian Yu, Cai-Xia Liu
Na Li, Chong Qiao, Yuan Lv, Tian Yang, Hao Liu, Wen-Qian Yu, Cai-Xia Liu, Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning Province, China
Na Li, Chong Qiao, Yuan Lv, Tian Yang, Hao Liu, Wen-Qian Yu, Cai-Xia Liu, Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Key Laboratory of Obstetrics and Gynecology of Higher Education of Liaoning Province, Shenyang 110004, Liaoning Province, China
Author contributions: Li N and Qiao C contributed equally to this work; Li N, Qiao C, Lv Y, and Liu CX designed the research; Li N, Liu H, and Yu WQ conducted the research; Li N, Lv Y, and Yang T analyzed the data; Li N, Yang T, Lv Y, and Qiao C wrote the paper; all authors read, reviewed, and approved the final manuscript; Liu CX had primary responsibility for final content.
Supported by the National Natural Science Foundation of China, No. 81701462 (to Lv Y); and the China National Health and Family Planning Commission, No. 201402006 (to Liu CX).
Informed consent statement: Written informed consent was obtained from the patient for publication of this case report and accompanying images.
Conflict-of-interest statement: The authors report no conflict of interest. The authors alone are responsible for the content and writing of the paper.
Data sharing statement: No additional data are available.
CARE Checklist (2016) statement: The authors have read the CARE Checklist statement, and the manuscript was prepared and revised according to the CARE Checklist statement.
Open-Access: This is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Cai-Xia Liu, MD, Doctor, Professor, Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, No. 36, Sanhao Street, Shenyang 110004, Liaoning Province, China. liucx@sj-hospital.org
Telephone: +86-24-9661543221 Fax: +86-24-9661543221
Received: December 25, 2018
Peer-review started: December 27, 2018
First decision: March 10, 2019
Revised: August 23, 2019
Accepted: September 9, 2019
Article in press: September 9, 2019
Published online: November 6, 2019
Abstract
BACKGROUND

Fetal akinesia deformation sequence (FADS) is a broad spectrum disorder with absent fetal movements as the unifying feature. The etiology of FADS is heterogeneous and mostly still unknown. A prenatal diagnosis of FADS relies on clinical features obtained by ultrasound and fetal muscle pathology. However, the recent advances of next-generation sequencing (NGS) can effectively provide a definitive molecular diagnosis.

CASE SUMMARY

A fetus presented after 24 wk and 6 d of gestation with absent fetal movements and multiple abnormal ultrasonographic signs. The mother had had a previous abortion due to a similarly affected fetus a year before. A clinical diagnosis of FADS was made. The parents refused cord blood examination and chose abortion. A molecular diagnosis of fetal muscle using NGS of genes found a compound heterozygous mutation in the MUSK gene: c.220C > T (chr9: 113449410 p.R74W) and c.421delC (chr9: 113457745 p.P141fs).

CONCLUSION

To our knowledge, this is the first report in China showing that a mutation in MUSK is associated with FADS. This supports previous finding that a lethal mutation of MUSK will cause FADS. A precise molecular diagnosis for genetic counseling and options for a prenatal diagnosis of FADS are very important, especially for recurrent FADS; this may also provide evidence for both prenatal and preimplantation genetic diagnoses.

Keywords: MUSK gene, Fetal akinesia deformation sequence, Joint contractures, Case report

Core tip: Fetal akinesia deformation sequence (FADS) is a broad spectrum disorder with absent fetal movements, and its etiology is heterogeneous. Mutations in genes expressed at the neuromuscular junction (NMJ) are increasingly recognized as important causes of FADS. MUSK is required for the formation and maintenance of the NMJ. Here we describe a compound heterozygous mutation of the MUSK gene that caused FADS in a Chinese fetus.