Annals of Dyslexia

, Volume 46, Issue 1, pp 241–257 | Cite as

Gender differences in cognitive abilities of opposite-sex and same-sex twin pairs with reading disabilty

  • Valerie S. Knopik
  • John C. DeFries
  • Maricela Alarcón
Part III Cognitive And Neurological Factors In Dyslexia


In order to compare the pattern of gender differences for cognitive measures in opposite-sex twin pairs to that in independent samples of twins from same-sex pairs, psychometric test data were obtained from four research-identified samples of children: (1) 96 pairs of opposite-sex fraternal twins in which at least one member of each pair is reading disabled; (2) 62 pairs of opposite-sex fraternal twins with no history of reading problems; (3) 167 males and 155 females from same-sex identical and same-sex fraternal twin pairs in which at least one member of each pair is reading disabled; and (4) a comparison sample of 126 males and 132 females from same-sex twin pairs with no history of reading problems. Results of multivariate analyses indicate that gender differences for cognitive measures are similar in twin pairs with and without reading disabilities. Moreover, a highly similar pattern of gender differences occurs for opposite-sex twin pairs who shared both prenatal and early postnatal influences and for independent samples of children from different families.


Twin Pair Read Disability Learn Disability Dyslexia Rapid Automatic Naming 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© The Orton Dyslexia Society 1996

Authors and Affiliations

  • Valerie S. Knopik
    • 1
  • John C. DeFries
    • 1
  • Maricela Alarcón
    • 1
  1. 1.Institute for Behavioral GeneticsUniversity of ColoradoBoulder

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