Recessive and Dominant De Novo ITPR1 Mutations Cause Gillespie Syndrome.
Am J Hum Genet
; 98(5): 971-980, 2016 May 05.
Article
em En
| MEDLINE
| ID: mdl-27108797
ABSTRACT
Gillespie syndrome (GS) is a rare variant form of aniridia characterized by non-progressive cerebellar ataxia, intellectual disability, and iris hypoplasia. Unlike the more common dominant and sporadic forms of aniridia, there has been no significant association with PAX6 mutations in individuals with GS and the mode of inheritance of the disease had long been regarded as uncertain. Using a combination of trio-based whole-exome sequencing and Sanger sequencing in five simplex GS-affected families, we found homozygous or compound heterozygous truncating mutations (c.4672C>T [p.Gln1558(∗)], c.2182C>T [p.Arg728(∗)], c.6366+3A>T [p.Gly2102Valfs5(∗)], and c.6664+5G>T [p.Ala2221Valfs23(∗)]) and de novo heterozygous mutations (c.7687_7689del [p.Lys2563del] and c.7659T>G [p.Phe2553Leu]) in the inositol 1,4,5-trisphosphate receptor type 1 gene (ITPR1). ITPR1 encodes one of the three members of the IP3-receptors family that form Ca(2+) release channels localized predominantly in membranes of endoplasmic reticulum Ca(2+) stores. The truncation mutants, which encompass the IP3-binding domain and varying lengths of the modulatory domain, did not form functional channels when produced in a heterologous cell system. Furthermore, ITPR1 p.Lys2563del mutant did not form IP3-induced Ca(2+) channels but exerted a negative effect when co-produced with wild-type ITPR1 channel activity. In total, these results demonstrate biallelic and monoallelic ITPR1 mutations as the underlying genetic defects for Gillespie syndrome, further extending the spectrum of ITPR1-related diseases.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Aniridia
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Ataxia Cerebelar
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Receptores de Inositol 1,4,5-Trifosfato
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Genes Dominantes
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Genes Recessivos
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Deficiência Intelectual
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Mutação
Limite:
Adolescent
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Child
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Child, preschool
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Female
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Humans
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Infant
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Male
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Newborn
Idioma:
En
Revista:
Am J Hum Genet
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
França