Novel candidate genes and regions for childhood apraxia of speech identified by array comparative genomic hybridization.

1] University of Wisconsin-Madison, Madison, Wisconsin, USA [2] Wisconsin State Laboratory of Hygiene, Madison, Wisconsin, USA.
Genetics in medicine: official journal of the American College of Medical Genetics (Impact Factor: 6.44). 07/2012; DOI: 10.1038/gim.2012.72
Source: PubMed

ABSTRACT Purpose:The goal of this study was to identify new candidate genes and genomic copy-number variations associated with a rare, severe, and persistent speech disorder termed childhood apraxia of speech. Childhood apraxia of speech is the speech disorder segregating with a mutation in FOXP2 in a multigenerational London pedigree widely studied for its role in the development of speech-language in humans.Methods:A total of 24 participants who were suspected to have childhood apraxia of speech were assessed using a comprehensive protocol that samples speech in challenging contexts. All participants met clinical-research criteria for childhood apraxia of speech. Array comparative genomic hybridization analyses were completed using a customized 385K Nimblegen array (Roche Nimblegen, Madison, WI) with increased coverage of genes and regions previously associated with childhood apraxia of speech.Results:A total of 16 copy-number variations with potential consequences for speech-language development were detected in 12 or half of the 24 participants. The copy-number variations occurred on 10 chromosomes, 3 of which had two to four candidate regions. Several participants were identified with copy-number variations in two to three regions. In addition, one participant had a heterozygous FOXP2 mutation and a copy-number variation on chromosome 2, and one participant had a 16p11.2 microdeletion and copy-number variations on chromosomes 13 and 14.Conclusion:Findings support the likelihood of heterogeneous genomic pathways associated with childhood apraxia of speech.Genet Med advance online publication 5 July 2012.

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