title: Common Genetic Variants in FOXP2 Are Not Associated with Individual Differences in Language Development.
abstract: Much of our current knowledge regarding the association of FOXP2 with speech and language development comes from singleton and small family studies where a small number of rare variants have been identified. However, neither genome-wide nor gene-specific studies have provided evidence that common polymorphisms in the gene contribute to individual differences in language development in the general population. One explanation for this inconsistency is that previous studies have been limited to relatively small samples of individuals with low language abilities, using low density gene coverage. The current study examined the association between common variants in FOXP2 and a quantitative measure of language ability in a population-based cohort of European decent (n = 812). No significant associations were found for a panel of 13 SNPs that covered the coding region of FOXP2 and extended into the promoter region. Power analyses indicated we should have been able to detect a QTL variance of 0.02 for an associated allele with MAF of 0.2 or greater with 80% power. This suggests that, if a common variant associated with language ability in this gene does exist, it is likely of small effect. Our findings lead us to conclude that while genetic variants in FOXP2 may be significant for rare forms of language impairment, they do not contribute appreciably to individual variation in the normal range as found in the general population.
authors.affiliation: Hearing, Language and Literacy, Murdoch Childrens Institute, Melbourne, Australia.|Dept. of Communication Sciences and Disorders, The University of Iowa, Iowa City, United States of America.
authors.forename: Kathryn L
authors.initials: KL
authors.lastname: Mueller
authors.affiliation: Dept. of Pediatrics, The University of Iowa, Iowa City, United States of America.
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Murray
authors.affiliation: Dept. of Psychiatry, The University of Iowa, Iowa City, United States of America.
authors.forename: Jacob J
authors.initials: JJ
authors.lastname: Michaelson
authors.affiliation: Dept. Psychology, Cornell University, New York, United States of America.
authors.forename: Morten H
authors.initials: MH
authors.lastname: Christiansen
authors.affiliation: Menzies Health Institute, Queensland, Australia.
authors.forename: Sheena
authors.initials: S
authors.lastname: Reilly
authors.affiliation: Dept. of Communication Sciences and Disorders, The University of Iowa, Iowa City, United States of America.
authors.forename: J Bruce
authors.initials: JB
authors.lastname: Tomblin
mesh_terms: D002648:Child; D003430:Cross-Sectional Studies; D051858:Forkhead Transcription Factors / Q000235:genetics*; D006801:Humans; D007804:Language Development; D015810:Linkage Disequilibrium; D008137:Longitudinal Studies; D020641:Polymorphism, Single Nucleotide; D044465:White People
chemical_list: C465448:FOXP2 protein, human; D051858:Forkhead Transcription Factors