Clinical and Molecular Genetic Studies of Specific Language Impairment

Abstract

Background: One important language gene is FOXP2 gene, a mutation of which affects language and speech in relatively rare and severe forms. However, certain genetic markers adjacent to FOXP2 gene are highly suspected to be involved in common forms of specific language impairment (SLI). Identification of these genetic loci related to SLI, may yield new insights into its causes, along with improved diagnosis, and treatment. Aim of the work: wastostudy the association of SLI to two genetic markers residing in the vicinity of FOXP2 gene, namely; the repeat unit GATA of D7S3052 marker, and GATT tetranucleotide repeats in intron 6 of CFTR gene. Subjects and methods: The current study included 50 SLI and 50 normal control subjects, aged 3 to 8 years. All participants were subjected to genetic molecular association study as well as detailed protocol of assessment including full history and examination, and evaluation of language skills and mental ability (IQ). Results: There was no difference between the SLI and normal groups regarding molecular results of GATT repeats of CFTR gene, and there was non-significant difference regarding results of GATA repeats of D7S3052 marker (P value>0.05). Conclusion:The association of SLI with D7S3052 marker at the vicinity of FOXP2 gene in current study is statistically non-significant. However, statistical significance of this association could be expected with larger number of cases, more diversity of SLI types and degrees, and more comprehensive procedures. Keywords: SLI, FOXP2 gene, D7S3052 marker, GATA repeats, Molecular study.