Case Report
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Sep 26, 2023; 11(27): 6618-6623
Published online Sep 26, 2023. doi: 10.12998/wjcc.v11.i27.6618
Compound heterozygous mutations in tripeptidyl peptidase 1 cause rare autosomal recessive spinocerebellar ataxia type 7: A case report
Rui-Han Liu, Xin-Yu Wang, Yuan-Yuan Jia, Xing-Chen Wang, Min Xia, Qiong Nie, Jia Guo, Qing-Xia Kong
Rui-Han Liu, Department of Pediatrics, Affiliated Hospital of Jining Medical University, Jining 272000, Shandong Province, China
Rui-Han Liu, College of TCM, Shandong University of Traditional Chinese Medicine, Jinan 250012, Shandong Province, China
Xin-Yu Wang, Qiong Nie, Jia Guo, Clinical Medical College, Jining Medical University, Jining 272000, Shandong Province, China
Yuan-Yuan Jia, Min Xia, Qing-Xia Kong, Department of Neurology, Affiliated Hospital of Jining Medical University, Jining 272000, Shandong Province, China
Xing-Chen Wang, Cheeloo College of Medicine, Shandong University, Jinan 250012, Shandong Province, China
Author contributions: Liu RH, Wang XY and Kong QX designed the study; Jia YY and Xia M collected the data; Nie Q and Guo J contributed to data analysis and interpretation; Liu RH, Wang XY and Wang XC drafted the manuscript; Kong QX and Liu RH contributed to revisions; All authors approved the final version of the manuscript.
Supported by Postdoctoral program of the Affiliated Hospital of Jining Medical University, No. JYFY303573; Health Commission of Shandong Province, No. 202006010928; Academician Lin He New Medicine in Jining Medical University, No. JYHL2018FMS05; Affiliated Hospital of Jining Medical University, No. 2018-BS-004.
Informed consent statement: Informed written consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016) and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article 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 NonCommercial (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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Qing-Xia Kong, PhD, Chief Physician, Doctor, Department of Neurology, Affiliated Hospital of Jining Medical University, No. 89 Guhuai Road, Jining 272000, Shandong Province, China. kxdqy8@sohu.com
Received: June 30, 2023
Peer-review started: June 30, 2023
First decision: August 9, 2023
Revised: August 15, 2023
Accepted: August 23, 2023
Article in press: August 23, 2023
Published online: September 26, 2023
Abstract
BACKGROUND

Spinocerebellar ataxia recessive type 7 (SCAR7) is a rare clinical manifestation beginning in childhood or adolescence. SCAR7 is caused by tripeptidyl peptidase 1 (TPP1) gene mutations, and presents with cerebellar ataxia, pyramidal signs, neurocognitive impairment, deep paresthesia, and cerebellar atrophy.

CASE SUMMARY

Here, we describe a 25-year-old female patient in China who presented with increasing difficulty walking, falling easily, shaking limbs, instability holding items, slurred speech, coughing when drinking, palpitations, and frequent hunger and overeating. Magnetic resonance imaging showed cerebellar atrophy. Whole exome sequencing detected two compound heterozygous mutations in the TPP1 gene: c.1468G>A p.Glu490Lys and c.1417G>A p.Gly473Arg. Considering the patient’s clinical presentation and genetic test results, we hypothesized that complex heterozygous mutations cause TPP1 enzyme deficiency, which may lead to SCAR7.

CONCLUSION

We report the first case of SCAR7 from China. We also identify novel compound heterozygous mutations in the TPP1 gene associated with SCAR7, expanding the range of known disease-causing mutations for SCAR7.

Keywords: Spinocerebellar ataxia recessive type 7, Tripeptidyl peptidase 1, Compound heterozygous variant, Case report

Core Tip: A Chinese woman presented with progressive walking difficulties, falling easily, slurred speech, and coughing when drinking. Magnetic resonance imaging revealed cerebellar atrophy. Whole exome sequencing detected novel compound heterozygous mutations in the tripeptidyl peptidase 1 gene. Clinical manifestations and bioinformatics analysis showed that the mutations caused spinocerebellar ataxia recessive type 7.