Examining the Genetic Underpinnings of Commonly Comorbid Language Disorders: Dyslexia and Language Impairment
Abstract
Written and verbal language are  vital to the development of communication skills. Unfortunately, disorders of  these traits—specifically reading disability (RD) and language impairment  (LI)—are common, leaving affected individuals at risk for adverse academic,  socioeconomic, and psychiatric outcomes. RD and LI are complex traits that  frequently co-occur, leading to the hypothesis that these disorders share  genetic contributors. 
 
In this webcast, John Eicher of  the Yale Child Health Research Center will discuss his search for shared  genetic contributors by performing two association scans: (1) Characterizing  the contribution of the DYX2 risk locus to RD, LI, and IQ; and (2) A genome  wide association study (GWAS) on individuals with comorbid RD and LI.
 
 
        Eicher found four DYX2 genes, including known  risk genes DCDC2 and KIAA0319, and new candidates FAM65B and CMAHP, were associated with RD, LI, and/or IQ. There was a  non-additive interaction between two risk variants in DCDC2 and KIAA0319 on  reading and language traits. The GWAS of comorbid RD and LI, produced  associations with markers in ZNF385D and COL4A2. Markers within NDST4 showed associations with LI. Eicher  replicated the association of ZNF385D in the Pediatric Imaging Neurocognitive Genetics (PING) study. Using diffusion  tensor imaging on PING subjects, ZNF385D markers were predictors of overall fiber tract volumes and global brain volume.  The contribution of DYX2 risk genes, DCDC2 and KIAA0319, and present evidence  for FAM65B and CMAHP as new candidate genes are confirmed. Additionally, a new  candidate gene for comorbid RD and LI, ZNF385D is implicated. Further study of ZNF385D,  a hypothesized transcription factor, should identify target genes of ZNF385D and its neural implications.
About the Presenter
John Eicher is a Ph.D. candidate at Yale University. John's thesis involved conducting GWAS research that seeks to determine if an association exists between reading disability and language impairment in humans. John was one of the first place winners in Golden Helix's first annual abstract competition.