Functional analyses of a novel splice variant in the CHD7 gene, found by next generation sequencing, confirm Its pathogenicity in a Spanish patient and diagnose him with CHARGE syndrome

Mutations in CHD7 have been shown to be a major cause of CHARGE syndrome, which presents many symptoms and features common to other syndromes making its diagnosis difficult. Next generation sequencing (NGS) of a panel of intellectual disability related genes was performed in an adult patient without...

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Detalles Bibliográficos
Autores: Villate Bejarano, Olatz, Ibarluzea, Nekane, Fraile-Bethencourt, Eugenia, Valenzuela-Palomo, Alberto, Velasco, Eladio, Grozeva, Detelina, Raymond, F. L., Botella, María P., Tejada, María Isabel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/196651
Acceso en línea:http://hdl.handle.net/10261/196651
Access Level:acceso abierto
Palabra clave:CHD7
CHARGE syndrome
Next generation sequencing
Alternative splicing
Descripción
Sumario:Mutations in CHD7 have been shown to be a major cause of CHARGE syndrome, which presents many symptoms and features common to other syndromes making its diagnosis difficult. Next generation sequencing (NGS) of a panel of intellectual disability related genes was performed in an adult patient without molecular diagnosis. A splice donor variant in CHD7 (c.5665 + 1G > T) was identified. To study its potential pathogenicity, exons and flanking intronic sequences were amplified from patient DNA and cloned into the pSAD® splicing vector. HeLa cells were transfected with this construct and a wild-type minigene and functional analysis were performed. The construct with the c.5665 + 1G > T variant produced an aberrant transcript with an insert of 63 nucleotides of intron 28 creating a premature termination codon (TAG) 25 nucleotides downstream. This would lead to the insertion of 8 new amino acids and therefore a truncated 1896 amino acid protein. As a result of this, the patient was diagnosed with CHARGE syndrome. Functional analyses underline their usefulness for studying the pathogenicity of variants found by NGS and therefore its application to accurately diagnose patients.