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Behavior Genetics

, Volume 41, Issue 1, pp 31–42 | Cite as

Genome Scan for Spelling Deficits: Effects of Verbal IQ on Models of Transmission and Trait Gene Localization

  • Kevin Rubenstein
  • Mark Matsushita
  • Virginia W. Berninger
  • Wendy H. Raskind
  • Ellen M. WijsmanEmail author
ORIGINAL RESEARCH

Abstract

Dyslexia is a complex learning disability with evidence for a genetic basis. Strategies that may be useful for dissecting its genetic basis include the study of component phenotypes, which may simplify the underlying genetic complexity, and use of an analytic approach that accounts for the multilocus nature of the trait to guide the investigation and increase power to detect individual loci. Here we present results of a genetic analysis of spelling disability as a component phenotype. Spelling disability is informative in analysis of extended pedigrees because it persists into adulthood. We show that a small number of hypothesized loci are sufficient to explain the inheritance of the trait in our sample, and that each of these loci maps to one of four genomic regions. Individual trait models and locations are a function of whether a verbal IQ adjustment is included, suggesting mediation through both IQ-related and unrelated pathways.

Keywords

Reading disability Linkage analysis Complex disorder MCMC Learning disability 

Notes

Acknowledgments

We are grateful to the families for their willingness to devote the time necessary to participate in these studies. We appreciate the expert help of Department of Educational Psychology graduate students Sylvia Abbott, Allison Brooks, Ana Rueda Brown, Rebecca Brooksher, Julie Busse, Kristina Byrd, Belle Chenault, Gerry Curtin, Kate Eschen, Julie Gibson, Sarah Hellewege, Diana Hoffer, Renee Hartman, Stephanie King, Linelle Milatchov, Stacy Ogier, Tanya Prather, James Rodriguez and Jared Taylor, in administering the test battery. We also thank Jennifer Thomson for her help in working with families, supervising the testers, and entering data; John Wolff for providing technical help in processing all the blood and DNA samples; and Hiep Nguyen for providing computer support. This study was supported by R01 HD054562 from the National Institute of Child Health and Development, and T32 GM081062 from the National Institute of General Medical Sciences. Genome scan genotyping was provided by N01-HV-48141 from the National Institute of Heart, Lung, and Blood to the Marshfield Genotyping Service.

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Kevin Rubenstein
    • 1
  • Mark Matsushita
    • 2
  • Virginia W. Berninger
    • 3
  • Wendy H. Raskind
    • 2
    • 4
  • Ellen M. Wijsman
    • 2
    • 5
    • 6
    Email author
  1. 1.Department of BiostatisticsUniversity of WashingtonSeattleUSA
  2. 2.Division of Medical Genetics, Department of MedicineUniversity of WashingtonSeattleUSA
  3. 3.Department of Educational PsychologyUniversity of WashingtonSeattleUSA
  4. 4.Department of Psychiatry and Behavioral SciencesUniversity of WashingtonSeattleUSA
  5. 5.SeattleUSA
  6. 6.Department of BiostatisticsUniversity of WashingtonSeattleUSA

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