Heterozygous nonsense ARX mutation in a family highlights the complexity of clinical and molecular diagnosis in case of chromosomal and single gene disorder co‐inheritance

Bibliographic Details
Title: Heterozygous nonsense ARX mutation in a family highlights the complexity of clinical and molecular diagnosis in case of chromosomal and single gene disorder co‐inheritance
Authors: Alice Traversa, Enrica Marchionni, Agnese Giovannetti, Maria L. Genovesi, Noemi Panzironi, Katia Margiotti, Giulia Napoli, Francesca Piceci Sparascio, Alessandro De Luca, Francesco Petrizzelli, Massimo Carella, Francesco Cardona, Silvia Bernardo, Lucia Manganaro, Tommaso Mazza, Antonio Pizzuti, Viviana Caputo
Source: Molecular Genetics & Genomic Medicine, Vol 8, Iss 8, Pp n/a-n/a (2020)
Publisher Information: Wiley, 2020.
Publication Year: 2020
Collection: LCC:Genetics
Subject Terms: 17q12 duplication syndrome, array‐CGH, ARX, clinical exome sequencing, corpus callosum, dual diagnosis, Genetics, QH426-470
More Details: Abstract Background Corpus callosum agenesis (ACC) is one of the most frequent Central Nervous System (CNS) malformations. However, genetics underlying isolated forms is still poorly recognized. Here, we report on two female familial cases with partial ACC. The proband shows isolated partial ACC and a mild neurodevelopmental phenotype. A fetus from a previous interrupted pregnancy exhibited a complex phenotype including partial ACC and the occurrence of a de novo 17q12 microduplication, which was interpreted as probably disease‐causing. Methods A trio‐based clinical exome sequencing (CES) was performed. Results Clinical exome sequencing data analysis led to identifying a heterozygous nonsense variant (NM_139058.3:c.922G>T; NP_620689.1:p.Glu308Ter) in the aristaless related homeobox gene (ARX) in the proband, with a putative de novo occurrence, producing a hypothetical protein lacking two essential domains. Sanger analysis confirmed the wild‐type status of both parents in different tissues, and disclosed the occurrence of the nonsense variant in the fetus of the interrupted pregnancy, suggesting a formerly unrecognized contribution of the ARX mutation to the fetus' phenotype and gonadal or gonadosomatic mosaicism in one of the parents. Conclusion This study describes the phenotype associated with a heterozygous loss of function variant in ARX. Moreover, it highlights the importance of investigating both chromosomal and genetic contributions in cases of complex syndromic phenotypes involving CNS.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2324-9269
Relation: https://doaj.org/toc/2324-9269
DOI: 10.1002/mgg3.1336
Access URL: https://doaj.org/article/dc2be2928238438d93f55dee99ed9483
Accession Number: edsdoj.2be2928238438d93f55dee99ed9483
Database: Directory of Open Access Journals
More Details
ISSN:23249269
DOI:10.1002/mgg3.1336
Published in:Molecular Genetics & Genomic Medicine
Language:English