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BMC Medical Genetics

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01-12-2020 | Spastic Paraplegia | Case report

Novel variants in AP4B1 cause spastic tetraplegia, moderate psychomotor development delay and febrile seizures in a Chinese patient: a case report

Authors: Wen-Cong Ruan, Jia Wang, Yong-Lin Yu, Yue-Ping Che, Li Ding, Chen-Xi Li, Xiao-Dong Wang, Hai-Feng Li

Published in: BMC Medical Genetics | Issue 1/2020

Abstract

Introduction

The AP4B1 gene encodes a subunit of adaptor protein complex-4 (AP4), a component of intracellular transportation of proteins which plays important roles in neurons. Bi-allelic mutations in AP4B1 cause autosomal recessive spastic paraplegia-47(SPG47).

Case presentation

Here we present a Chinese patient with spastic tetraplegia, moderate psychomotor development delay and febrile seizures plus. Brain MRIs showed dilated supratentorial ventricle, thin posterior and splenium part of corpus callosum. The patient had little progress through medical treatments and rehabilitating regimens. Whole exome sequencing identified novel compound heterozygous truncating variants c.1207C > T (p.Gln403*) and c.52_53delAC (p.Cys18Glnfs*7) in AP4B1 gene. Causal mutations in AP4B1 have been reported in 29 individuals from 22 families so far, most of which are homozygous mutations.

Conclusions

Our study enriched the genetic and phenotypic spectrum of SPG47. Early discovery, diagnosis and proper treatment on the conditions generally increase chances of improvement on the quality of life for patients.

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Title: Novel variants in AP4B1 cause spastic tetraplegia, moderate psychomotor development delay and febrile seizures in a Chinese patient: a case report
Authors: Wen-Cong Ruan
Jia Wang
Yong-Lin Yu
Yue-Ping Che
Li Ding
Chen-Xi Li
Xiao-Dong Wang
Hai-Feng Li
Publication date: 01-12-2020
Publisher: BioMed Central
Keywords: Spastic Paraplegia
Tetraparesis
Febrile Seizure
Published in: BMC Medical Genetics / Issue 1/2020
Electronic ISSN: 1471-2350
DOI: https://doi.org/10.1186/s12881-020-0988-3

At a glance: The STEP trials

Springer Medicine

Novel variants in AP4B1 cause spastic tetraplegia, moderate psychomotor development delay and febrile seizures in a Chinese patient: a case report

Abstract

Introduction

Case presentation

Conclusions

At a glance: The STEP trials

Springer Medicine

Abstract

Introduction

Case presentation

Conclusions

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