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Case Reports
. 2020 Nov 4:2020:7163038.
doi: 10.1155/2020/7163038. eCollection 2020.

A Report on a Family with TMTC3-Related Syndrome and Review

Sayeeda Hana  1 , Deepak Karthik  2 , Jingxuan Shan  2   3 , Stephany El Hayek  1 , Lotfi Chouchane  2   3   4 , André Megarbane  5   6   7
Affiliations
Case Reports

A Report on a Family with TMTC3-Related Syndrome and Review

Sayeeda Hana et al. Case Rep Med. .

Abstract

Recessive mutations in the TMTC3 gene have been reported in thirteen patients to date exhibiting development delay, intellectual disability (ID), seizures, and muscular hypotonia, accompanied occasionally by neuronal migration defects expressed as either cobblestone lissencephaly or periventricular hypertopia. Here, we report a new case of a TMTC3-related syndrome in a Lebanese family with two affected siblings showing severe psychomotor retardation, intellectual disability, microcephaly, absence of speech, muscular hypotonia, and seizures. Whole exome sequencing revealed a homozygous pathogenic variant c.211 C > T (p.R71C) in the TMTC3 gene in both siblings. A review of the literature on TMTC3-related syndrome and its causal mutations is provided.

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Conflict of interest statement

The authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
(a) Pedigree of the affected family. (b) Sanger sequencing electropherograms showing the TMTC3 variant c.211C > T (red box) at a heterozygous state in parents and at a homozygous state in the affected daughters. (c) Photographs of the patients.
Figure 2
Figure 2
(a) ClustalW alignment of TMTC3 residues showing conservation of the p.71R residue across diverse species. (b) Lollipop plot of the known mutations on the TMTC3 protein.
See this image and copyright information in PMC

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