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A Novel Frameshift Variant of the MITF Gene in a Chinese Family with Waardenburg Syndrome Type 2.

ABSTRACT: Waardenburg syndrome (WS) is a rare genetic disorder characterized by varying combinations of sensorineural hearing loss and abnormal pigmentation involving the hair, skin and iris. WS is classified into 4 subtypes (WS1-WS4) based on additional symptoms. WS2 is characterized by the absence of additional symptoms and is mainly attributed to variants in the microphthalmia-associated transcription factor (MITF) gene. We detected a novel frameshift variant c.1025_1032delGGAACAAG (NM_198159) of MITF in 5 patients with WS2 from the same Chinese family by using targeted next-generation sequencing and Sanger sequencing. Phenotypic and genotypic analyses of the family members suggested that this novel variants was pathogenic. Our finding expands the spectrum of MITF variants.

SUBMITTER: Li Y

PROVIDER: S-EPMC8339487 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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A Novel Frameshift Variant of the MITF Gene in a Chinese Family with Waardenburg Syndrome Type 2.

Li Ying Y Xu Yajuan Y Li Genxia G Chen Kang K Yu Haiyang H Gao Jinshuang J Tian Weifang W Liu Yuehua Y Liu Pingping P Zhang Linlin L Zhang Zhan Z

Molecular syndromology 20210614 4

Waardenburg syndrome (WS) is a rare genetic disorder characterized by varying combinations of sensorineural hearing loss and abnormal pigmentation involving the hair, skin and iris. WS is classified into 4 subtypes (WS1-WS4) based on additional symptoms. WS2 is characterized by the absence of additional symptoms and is mainly attributed to variants in the microphthalmia-associated transcription factor (MITF) gene. We detected a novel frameshift variant c.1025_1032delGGAACAAG (NM_198159) o ...[more]

PMID: 34421503

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Frameshift variant in MITF gene in a large family with Waardenburg syndrome type II and a co-segregation of a C2orf74 variant.

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Targeted next-generation sequencing identified a novel variant of SOX10 in a Chinese family with Waardenburg syndrome type 2.

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