
Title: Multipoint genome-wide linkage scan for nonword repetition in a multigenerational family further supports chromosome 13q as a locus for verbal trait disorders.
Legend: Multipoint linkage results conditioned on impaired NWR at chromosome 13. Genes and associated SNPs under the highest linkage peak of LOD = 4.35, between 52 and 55 cM spanning physical positions 48–53.5 Mb on reference genome assembly build GRCh37/hg19
Citation: Truong, D. T., Shriberg, L. D., Smith, S. D., Chapman, K. L., Scheer-Cohen, A. R., DeMille, M. M. C., Adams, A. K., Nato, A. Q., Wijsman, E. M., Eicher, J. D., & Gruen, J. R. (2016). Multipoint genome-wide linkage scan for nonword repetition in a multigenerational family further supports chromosome 13q as a locus for verbal trait disorders. Human Genetics, 135, 1329-1341.
Abstract: Verbal trait disorders encompass a wide range of conditions and are marked by deficits in five domains that impair a person’s ability to communicate: speech, language, reading, spelling, and writing. Nonword repetition is a robust endophenotype for verbal trait disorders that is sensitive to cognitive processes critical to verbal development, including auditory processing, phonological working memory, and motor planning and programming. In the present study, we present a six-generation extended pedigree with a history of verbal trait disorders. Using genome-wide multipoint variance component linkage analysis of nonword repetition, we identified a region spanning chromosome 13q14–q21 with LOD = 4.45 between 52 and 55 cM, spanning approximately 5.5 Mb on chromosome 13. This region overlaps with SLI3, a locus implicated in reading disability in families with a history of specific language impairment. Our study of a large multigenerational family with verbal trait disorders further implicates the SLI3 region in verbal trait disorders. Future studies will further refine the specific causal genetic factors in this locus on chromosome 13q that contribute to language traits.
About the Lab: Speech Sound Disorders (SSD) put children at risk for literacy development, reduced peer acceptance, and limitations in vocational options. Our research goals are to understand the causal pathways that lead to subtypes of SSD so that clinicians can select the appropriate intervention approach for each child, and researchers can conduct studies leading to the prevention of some subtypes of SSD. We are studying genomic, motoric, and speech processing correlates of idiopathic SSD and SSD in the context of complex neurodevelopmental disorders (e.g., autism, Down syndrome, fragile X syndrome, galactosemia, FOXP2 disruptions, 22q11.2 deletion, 16p11.2 deletions and duplications).