title: DCDC2, KIAA0319 and CMIP are associated with reading-related traits.
abstract: BACKGROUND
  Several susceptibility genes have been proposed for dyslexia (reading disability; RD) and specific language impairment (SLI). RD and SLI show comorbidity, but it is unclear whether a common genetic component is shared.
  
  
  METHODS
  We have investigated whether candidate genes for RD and SLI affect specific cognitive traits or have broad effect on cognition. We have analyzed common risk variants within RD (MRPL19/C2ORF3, KIAA0319, and DCDC2) and language impairment (CMIP and ATP2C2) candidate loci in the Avon Longitudinal Study of Parents and Children cohort (n = 3725), representing children born in southwest England in the early 1990s.
  
  
  RESULTS
  We detected associations between reading skills and KIAA0319, DCDC2, and CMIP. We show that DCDC2 is specifically associated with RD, whereas variants in CMIP and KIAA0319 are associated with reading skills across the ability range. The strongest associations were restricted to single-word reading and spelling measures, suggesting that these genes do not extend their effect to other reading and language-related skills. Inclusion of individuals with comorbidity tends to strengthen these associations. Our data do not support MRPL19/C2ORF3 as a locus involved in reading abilities nor CMIP/ATP2C2 as genes regulating language skills.
  
  
  CONCLUSIONS
  We provide further support for the role of KIAA0319 and DCDC2 in contributing to reading abilities and novel evidence that the language-disorder candidate gene CMIP is also implicated in reading processes. Additionally, we present novel data to evaluate the prevalence and comorbidity of RD and SLI, and we recommend not excluding individuals with comorbid RD and SLI when designing genetic association studies for RD.
authors: Wellcome Trust Centre for Human Genetics, University of Oxford, UK.
authors: Tom S
authors: TS
authors: Scerri
authors: Andrew P
authors: AP
authors: Morris
authors: Lyn-Louise
authors: LL
authors: Buckingham
authors: Dianne F
authors: DF
authors: Newbury
authors: Laura L
authors: LL
authors: Miller
authors: Anthony P
authors: AP
authors: Monaco
authors: Dorothy V M
authors: DV
authors: Bishop
authors: Silvia
authors: S
authors: Paracchini
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000293:Adolescent; D002352:Carrier Proteins / Q000235:genetics*; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology; D015897:Comorbidity; D004410:Dyslexia / Q000453:epidemiology / Q000235:genetics*; D004739:England / Q000453:epidemiology; D005260:Female; D056726:Genetic Association Studies; D005838:Genotype; D006801:Humans; D007802:Language; D007806:Language Disorders / Q000453:epidemiology / Q000235:genetics*; D008297:Male; D008869:Microtubule-Associated Proteins / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D015995:Prevalence; D011932:Reading
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C540426:CMIP protein, human; D002352:Carrier Proteins; C510451:DCDC2 protein, human; C500377:KIAA0319 protein, human; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins