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Genes, environment, and dyslexia the 2005 Norman Geschwind memorial lecture

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Abstract

This article presents an overview of some methods and results from our continuing studies of genetic and environmental influences on dyslexia, and on individual differences across the normal range that have been conducted over the past 25 years in the Colorado Learning Disabilities Research Center (CLDRC) and in related projects. CLDRC investigators compare the similarities of identical twin pairs who share all their genes and fraternal twins who share half their segregating genes to assess the balance of genetic, shared family environment, and nonshared environment influences on dyslexia and on individual differences across the normal range. We have learned that among the children we have studied in Colorado, group deficits in reading (dyslexia) and individual differences in reading across the normal range are primarily due to genetic influences, and these genetic influences are often shared with some of the same genetic influences on deficits and individual differences in language and ADHD. We have also learned from our molecular-genetic linkage studies that there are regions on several chromosomes likely to contain genes that influence dyslexia. Several specific genes within these regions have been tentatively identified through molecular-genetic association analyses, but much more research is needed to understand the pathways among specific genes, regions of noncoding DNA that regulate the activity of those genes, the brain, and dyslexia. I conclude with a discussion of our research on individual differences in early reading development, on the role of early learning constraints in dyslexia, and on how genetic influences are expressed through their interaction and correlation with the environment.

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References

  • Blakeslee, S. (2005). Scientists tie two additional genes to dyslexia. The New York Times, October 29, 2005.

  • Boada, R., Willcutt, E. G., Tunick, R. A., Chhabildas, N. A., Olson, R. K., DeFries, J. C., & Pennington, B. F. (2002). A twin study of the etiology of high reading ability. Reading and Writing: An Interdisciplinary Journal, 15, 683–707.

    Article  Google Scholar 

  • Byrne, B., Fielding-Barnsley, R., & Ashley, L. (2000). Effects of phoneme identity training after six years: Outcome level distinguished from rate of response. Journal of Educational Psychology, 92, 659–667.

    Article  Google Scholar 

  • Byrne, B., Olson, R. K., Samuelsson, S., Wadsworth, S., Corley, R., DeFries, J. C., & Willcutt, E. (2006). Genetic and environmental influences on early literacy. Journal of Research in Reading, 29, 33–49.

    Article  Google Scholar 

  • Byrne, B., Samuelsson, S., Wadsworth, S., Hulslander, J., Corley, R., DeFries, J. C., Quain, P., Willcutt, E., & Olson, R. K. (in press). Longitudinal twin study of early literacy development: Preschool through Grade 1. Reading and Writing: An Interdisciplinary Journal.

  • Cardon, L. R., Smith, S. D., Fulker, D. W., Kimberling, W. J., Pennington, B. F., & DeFries, J. C. (1994). Quantitative trait locus for reading disability on chromosome 6. Science, 266(5183), 276–279.

    Article  Google Scholar 

  • Castles, A., Datta, H., Gayán, J., & Olson, R. K. (1999). Varieties of developmental reading disorder: Genetic and environmental influences. Journal of Experimental Child Psychology, 72, 73–94.

    Article  Google Scholar 

  • Compton, D. L., Davis, C. J., DeFries, J. C., Gayán, J., & Olson, R. K. (2001). Genetic and environmental influences on reading and RAN: An overview of results from the Colorado twin study. In M. Wolf (Ed.), Conference proceedings of the dyslexia research foundation conference in extraordinary brain series: Time, fluency, and developmental dyslexia (pp. 277–303). Baltimore, MD: York Press.

    Google Scholar 

  • Cope, N., Harold, D., Hill, G., Moskvina, V., Stevenson, J., Holmans, P., Owen, M. J., O’Donovan, M. C., & Williams, J. (2005) Strong evidence that KIAA0319 on chromosome 6p is a susceptibility gene for developmental dyslexia. American Journal of Human Genetics, 76, 581–591.

    Article  Google Scholar 

  • Davis, G., & Davis, N. (2005). Life lessons from a successful dyslexic. Presentation at the annual conference of the International Dyslexia Association, Denver, CO, November 10, 2005.

  • Deffenbacher, K. E., Kenyon, J. B., Hoover, D. M., Olson, R. K., Pennington, B. F., DeFries, J. C., & Smith, S. D. (2004). Refinement of the 6p21.3 QTL influencing dyslexia: Linkage and association analysis. Human Genetics, 115, 128–138.

    Article  Google Scholar 

  • DeFries, J. C., & Fulker, D. W. (1985). Multiple regression analysis of twin data. Behavior Genetics, 15, 467–473.

    Article  Google Scholar 

  • DeFries, J. C., & Fulker, D. W. (1988). Multiple regression analysis of twin data: Etiology of deviant scores versus individual differences. Acta Geneticae Medicae et Gemellologiae, 37, 205–216.

    Google Scholar 

  • DeFries, J. C., Fulker, D. W., & LaBuda, M. C. (1987). Evidence for a genetic aetiology in reading disability of twins. Nature, 329, 537–539.

    Article  Google Scholar 

  • Dunn, L. M., & Markwardt, F. C. (1970). Peabody individual achievement test. Circle Pines, MN: American Guidance Service.

    Google Scholar 

  • Fisher, S. E., & DeFries, J. C. (2002). Developmental dyslexia: Genetic dissection of a complex cognitive trait. Nature Reviews Neuroscience, 3, 767–780.

    Article  Google Scholar 

  • Francks, C., Paracchini, S., Smith, S. D., Richardson, A. J., Scerri, T. S., Cardon, L. R., Marlow, A. J., MacPhie, I. L., Walker, J., Pennington, B. F., Fisher, S. E., Olson, R. K., DeFries, J. C., Stein, J. F., & Monaco, A. P. (2004). A 77 kilobase region of chromosome 6p22.2 is associated with dyslexia in families from the United Kingdom and from the United States. American Journal of Human Genetics, 75, 1046–1058.

    Article  Google Scholar 

  • Friend, A., DeFries, J. C., Wadsworth, S. J., & Olson, R. K. (in press). Developmental differences in the genetic etiology of reading and spelling disabilities. Behavior Genetics (Abstract).

  • Galaburda, A. M. (2005). Norman Geschwind memorial lecture: Dyslexia—a molecular disorder of neuronal migration. Annals of Dyslexia, 55(2), 151–165.

    Google Scholar 

  • Gayán, J., Willcutt, E. G., Fisher, S. E., Francks, C., Cardon, L. R., Olson, R. K., Pennington, B. F., Smith, S. D., Monaco, A. P., & DeFries, J. C. (2005). Bivariate linkage scan for reading disability and attention-deficit/hyperactivity disorder localizes pleiotropic loci. Journal of Child Psychology and Psychiatry, 46, 1045–1056.

    Article  Google Scholar 

  • Gayán, J., & Olson, R. K. (2001). Genetic and environmental influences on orthographic and phonological skills in children with reading disabilities. Developmental Neuropsychology, 20(2), 487–511.

    Article  Google Scholar 

  • Gayán, J., & Olson, R. K. (2003). Genetic and environmental influences on individual differences in printed word recognition. Journal of Experimental Child Psychology, 84, 97–123.

    Article  Google Scholar 

  • Geschwind, N. (1981). A reaction to the conference on sex differences and dyslexia. In A. Ansara., N. Geschwind, A. Galaburda, M. Albert, & N. Gartrell (Eds.), Sex differences in dyslexia (pp. xiii-xviii). Towson, MD: Orton Dyslexia Society.

    Google Scholar 

  • Grigorenko, E. L., Wood, F. B., Meyer, M. S., Hart, L. A., Speed, W. C., Shuster, A., & Pauls, D. L. (1997). Susceptibility loci for distinct components of developmental dyslexia on chromosome 6 and 15. American Journal of Human Genetics, 60, 27–39.

    Google Scholar 

  • Grigorenko, E. L., Wood, F. B., Meyer, M. S., & Pauls, D. L. (2000). Chromosome 6p influences on different dyslexia-related cognitive processes: Further confirmation. American Journal of Human Genetics, 66(2), 715–723.

    Article  Google Scholar 

  • Harlaar, N., Spinath, F. M., Dale, P. S., & Plomin, R. (2005). Genetic influences on early word recognition abilities and disabilities: A study of 7-year-old twins. Journal of Child Psychology and Psychiatry, 46, 373 - 384.

    Article  Google Scholar 

  • Hawke, J. L., Wadsworth, S. J., Olson, R. K., & DeFries, J. C. (in press). Etiology of reading difficulties as a function of gender and severity. Reading and Writing: An Interdisciplinary Journal.

  • Hoover, W. A., & Gough, P. B. (1990). The simple view of reading. Reading & Writing: An Interdisciplinary Journal, 2,127–160.

    Article  Google Scholar 

  • Horner, J. (2005). Dyslexia talents and dinosaur fossils: Personal observations. Presentation at the annual conference of the International Dyslexia Association, Denver, CO, November 11, 2005.

  • Igo, R. P., Chapman, N. H., Berninger, V. W., Matsushita, M., Brkanac, Z., Rothstein, J. H., Holtzman, T., Nielsen, K., Raskind, W. H., & Wijsman, E. M. (2006). Genomewide scan for real-word reading subphenotypes of dyslexia: Novel chromosome 13 locus and genetic complexity. American Journal of Medical Genetics Part B (Neuropsychiatric Genetics) 141B, 15–27.

    Article  Google Scholar 

  • Kaplan, D. E., Gayán, J., Ahn, J., Won, T. W., Pauls, D., Olson, R., DeFries, J. C., Wood, F., Pennington, B., Page, G., Smith, S. D., & Gruen, J. R. (2002). Evidence for linkage and association with reading disability on 6P21.3–22. American Journal of Human Genetics, 70, 1287–1298.

    Article  Google Scholar 

  • Keenan, J. M., Betjemann, R., Wadsworth, S. J., DeFries, J. C., & Olson, R. K. (2006). Genetic and environmental influences on reading and listening comprehension. Journal of Research in Reading, 29, 75–91.

    Article  Google Scholar 

  • Knopik, V. S., Alarcon, M., & DeFries, J. C. (1997). Comorbidity of mathematics and reading deficits: Evidence for a genetic etiology. Behavior Genetics, 27, 447–453.

    Article  Google Scholar 

  • Leach, J. M., Scarborough, H. S., & Rescorla, L. (2003). Late-emerging reading disabilities. Journal of Educational Psychology, 95, 211–224.

    Article  Google Scholar 

  • Lyon, G. R., Fletcher, J. M., Shaywitz, S. E., Shaywitz, B. A., Torgesen, J. K., Wood, F. B., Jr., Schulte, A., & Olson, R. K. (2001). Rethinking learning disabilities. In C. E. Finn, A. J. Rotherham, & C. R. Hokanson, Jr. (Eds.), Rethinking special education for a new century (pp. 259–287). Washington, DC: Thomas B. Fordham Foundation and Progressive Policy Institute.

    Google Scholar 

  • Marlow, A. J., Fisher, S. E., Francks, C., MacPhie, I. L., Cherny, S. S., Richardson, A. J. et al. (2003). Use of multivariate linkage analysis for dissection of a complex trait. American Journal of Human Genetics, 72, 561–570.

    Article  Google Scholar 

  • McCoach, D. B., O’Connell, A. A., Reis, S. M., & Levitt, H. A. (2006). Growing readers: A hierarchical linear model of children’s reading growth during the first two years of school. Journal of Educational Psychology, 98, 14–28.

    Article  Google Scholar 

  • Mehta, P. D., Foorman, B. R., Branum-Martin, L., & Taylor, P. W. (2005). Literacy as a unidimensional multilevel construct: Validation, sources of influence, and implications in a longitudinal study in grades 1–4. Scientific Studies of Reading, 9, 85–116.

    Article  Google Scholar 

  • Meng, H., Hager, K., Held, M., Page, G. P., Olson, R. K., Pennington, B. F., DeFries, J. C., Smith, S. D., & Gruen, J. R. (2005). TDT-association analysis of EKN1 and dyslexia in a Colorado twin cohort. Human Genetics, 118(1), 87–90.

    Article  Google Scholar 

  • Meng, H., Smith, S. D., Hager, K., Held, M., Liu, J., Olson, R. K., Pennington, B. F., DeFries, J. C., Gelernter, J., O’Reilly-Pol, T., Somlo, S., Skudlarski, P., Shaywitz, S. E., Shaywitz, B. A., Marchione, K., Wang, Y., Paramasivam, M., LoTurco, J. J., Page, G. P., & Gruen, J. R. (2005). DCDC2 is associated with reading disability and modulates neuronal migration in the brain. Proceedings of the National Academy of Science of the United States of America, 102(47), 17053–17058.

    Article  Google Scholar 

  • Moats, L., & Foorman, B. R. (2003). Measuring teachers’ content knowledge of language and reading. Annals of Dyslexia, 53, 23–45.

    Google Scholar 

  • Moffitt, T. E., Caspi, A., & Rutter, M. (2005). Strategy for investigating interactions between measured genes and measured environments. Archives of General Psychiatry, 62(5), 473–481.

    Article  Google Scholar 

  • Morgan, P. L., Fuchs, D., Compton, D. L., Cordray, D. S., & Fuchs, L. (in press). Does early reading failure decrease children’s reading motivation? Journal of Learning Disabilities.

  • Olson, R. K. (2002). Dyslexia: Nature and nurture. Dyslexia, 8, 143–159.

    Article  Google Scholar 

  • Olson, R. K., Datta, H., Gayán, J., & DeFries, J. C. (1999). A behavioral-genetic analysis of reading disabilities and component processes. In R. M. Klein & P. A. McMullen (Eds.), Converging methods for understanding reading and dyslexia (pp. 133–153). Cambridge MA: MIT Press.

    Google Scholar 

  • Olson, R. K., Lefly, D., Byrne, B., Samuelsson, S., Corley, R., Hulslander, J., Wadsworth, S., Willcutt, E., & DeFries, J. C. (2006). School and genetic influences on early reading and related skills. Paper presented at the meeting of the Society for the Scientific Study of Reading, Vancouver, B.C., July 6.

  • Olson, R. K., & Wise, B. (2006). Computer-based remediation for reading and related phonological disabilities. In M. McKenna, L. Labbo, R. Kieffer, & D. Reinking (Eds.), Handbook of literacy and technology, Vol. 2. (pp. 57–74). Mahwah, NJ: Lawrence Erlbaum.

    Google Scholar 

  • Olson, R. K., Wise, B., Conners, F., Rack, J., & Fulker, D. (1989). Specific deficits in component reading and language skills: Genetic and environmental influences. Journal of Learning Disabilities, 22, 339–348.

    Article  Google Scholar 

  • Paracchini, S., Thomas, A., Castro, S., Lai, C., Paramasivam, M., Wang, Y., Keating, B. J., Taylor, J. M., Hacking, D. F., Scerri, T., Francks, C., Richardson, A. J., Wade-Martins, R., Stein, J. F., Knight, J. C., Copp, A. J., LoTurco, J., & Monaco, A. P. (2006). The chromosome 6p22 haplotype associated with dyslexia reduces the expression of KIAA0319, a novel gene involved in neuronal migration. Human Molecular Genetics, 15(10), 1659–1666.

    Article  Google Scholar 

  • Pennington, B. F. (2006). From single to multiple deficit models of developmental disorders. Cognition, 101, 385–413.

    Article  Google Scholar 

  • Pennington, B. F., & Olson, R. K. (2005). Genetics of dyslexia. In M. Snowling, C. Hulme, & M. Seidenberg (Eds.), The science of reading: A handbook (pp. 453–472). Oxford, UK: Blackwell Publishing.

    Google Scholar 

  • Petrill, S. A., Deater-Deckard, K., Thompson, L. A., Schatschneider, C., DeThorne, L. S., & Vandenbergh, D. J. (in press). Longitudinal genetic analysis of early reading: The Western Reserve Reading Project. Reading and Writing: An Interdisciplinary Journal.

  • Plomin, R., & Kovas, Y. (2005). Generalist genes and learning disabilities. Psychological Bulletin, 131(4), 592–617.

    Article  Google Scholar 

  • Rack, J. P., Snowling, M. J., & Olson, R. K. (1992). The nonword reading deficit in developmental dyslexia: A review. Reading Research Quarterly, 27, 28–53.

    Article  Google Scholar 

  • Rawls, J. (1976). A theory of justice. Cambridge, MA: Harvard University Press.

    Google Scholar 

  • Rodgers, B. (1983). The identification and prevalence of specific reading retardation. British Journal of Educational Psychology, 53, 369–373.

    Google Scholar 

  • Sadoski, M., & Wilson, V. L. (2006). Effects of a theoretically based large-scale reading intervention in a multicultural urban school district. American Educational Research Journal, 43, 137–154.

    Article  Google Scholar 

  • Samuelsson, S., Byrne, B., Wadsworth, S., Corley, R., DeFries, J. C., Willcutt, E., Hulslander, J., & Olson, R. K. (in press). Genetic and environmental influences on pre-reading skills and early reading and spelling development: A comparison among the United States, Australia, and Scandinavia. Reading and Writing: An Interdisciplinary Journal.

  • Samuelsson, S., Byrne, B., Quain, P., Corley, R., DeFries, J. C., Wadsworth, S., Willcutt, E., & Olson, R. K. (2005). Environmental and genetic influences on pre-reading skills in Australia, Scandinavia, and the U.S. Journal of Educational Psychology, 97, 705–722.

    Article  Google Scholar 

  • Samuelsson, S., Olson, R. K., Byrne, B., Willcutt, E., Hulslander, J., Wadsworth, S., & DeFries, J. C. (2006). Genetic and environmental influences on early literacy development in Australia, Scandinavia, and the United States. Paper presented at the meeting of the Society for the Scientific Study of Reading, Vancouver, B.C., July 6.

  • Schumacher, J., Anthoni, H., Dahdouh, F., Konig, I. R., Hillmer, A. M., Kluck, N., Manthey, M., Plume, E., Warnke, A., Remschmidt, H., Hulsmann, J., Cichon, S., Lindgren, C. M., Propping, P., Zucchelli, M., Ziegler, A., Peyrard-Janvid, M., Schulte-Korne, G., Nothen, M. M., & Kere, J. (2006). Strong genetic evidence of DCDC2 as a susceptibility gene for dyslexia. American Journal of Human Genetics, 78(1), 52–62.

    Article  Google Scholar 

  • Shanahan, M., Yerys, B., Scott, A., Willcutt, E., DeFries, J. C., & Olson, R. K. et al. (in press). Processing speed deficits in attention deficit hyperactivity disorder and reading disability. Journal of Abnormal Child Psychology.

  • Shaywitz, S. E., Escobar, M. D., Shaywitz, B., Fletcher, J. M. et al. (1992). Evidence that dyslexia may represent the lower tail of a normal distribution of reading ability. New England Journal of Medicine, 326(3), 145–150.

    Article  Google Scholar 

  • Smith, S. D., Kimberling, W. J., & Pennington, B. F. (1991). Screening for multiple genes influencing dyslexia. Reading and Writing: An Interdisciplinary Journal, 3, 285–298.

    Article  Google Scholar 

  • Smith, S. D., Kimberling, W. J., Pennington, B. F., & Lubs, H. A. (1983). Specific reading disability: identification of an inherited form through linkage analysis. Science, 219(4590), 1345–1347.

    Article  Google Scholar 

  • Snowling, M. J., & Hayiou-Thomas M. E. (2006). The dyslexia spectrum: Continuities between reading, speech, and language impairments. Topics in Language Disorders, 26, 108–124.

    Article  Google Scholar 

  • Stanovich, K. E. (1986). Matthew effects in reading: Some consequences of individual differences in the acquisition of literacy. Reading Research Quarterly, 21, 360–407.

    Article  Google Scholar 

  • Stevenson, J. (1992). Identifying sex differences in reading disability: Lessons from a twin study. Reading and Writing: An Interdisciplinary Journal, 4, 307–326.

    Article  Google Scholar 

  • Taipale, M., Kaminen, N., Nopola-Hemmi, J., Haltia, T., Myllyluoma, B., Lyytinen, H., Muller, K., Kaaranen, M., Lindsberg, P. J., Hannula-Jouppi, K., & Kere, J. (2003). A candidate gene for developmental dyslexia encodes a nuclear tertatricopeptide repeat domain protein dynamically regulated in the brain. Proceedings of the National Academy of Sciences of the United States of America, 20, 11553–11558.

    Article  Google Scholar 

  • Torgesen, J., Wagner, R., & Rashotte, C. A. (1999). A test of word reading efficiency (TOWRE). Austin, TX: PRO-ED.

    Google Scholar 

  • Turkheimer, E., Haley, A., Waldron, M., D’Onofrio, B., & Gottesman, I. (2003). Socioeconomic status modifies heritability of IQ in young children. Psychological Science, 14(6), 623–628.

    Article  Google Scholar 

  • Vaughn, S., & Fuchs, L. S. (2003). Redefining learning disabilities as inadequate response to instruction: The promise and potential problems. Learning Disabilities Research & Practice, 18, 137–146.

    Article  Google Scholar 

  • Wadsworth, S. J., & DeFries, J. C. (2005). Genetic etiology of reading difficulties in boys and girls. Twin Research and Human Genetics, 8(6), 594–601.

    Article  Google Scholar 

  • Wadsworth, S. J., Olson, R. K., Pennington, B. F., & DeFries, J. C. (2000). Differential genetic etiology of reading disability as a function of IQ. Journal of Learning Disabilities, 33, 192–199.

    Google Scholar 

  • Wechsler, D. (1991). Examiners’ manual: The Wechsler intelligence scale for children—3rd edition. San Antonio, TX: The Psychological Corporation.

    Google Scholar 

  • West, T. (2005). Geniuses who hated school: Seeing what others do not see. Presentation at the annual conference of the International Dyslexia Association, November 11, 2005.

  • Wigfield, A., & Guthrie, J. T. (1997). Relations of children’s motivation for reading and the breadth of their reading. Journal of Educational Psychology, 89, 420–432.

    Article  Google Scholar 

  • Willcutt, E. G., DeFries, J. C., Pennington, B. F., Smith, S. D., Cardon, L. R., & Olson, R. K. (2003). Genetic etiology of comorbid reading difficulties. In R. Plomin, J. C. DeFries, I. W. Craig, & P. McGuffin (Eds.), Behavioral genetics in the postgenomic era (pp. 227–246). Washington, DC: American Psychological Association.

    Chapter  Google Scholar 

  • Wise, B. W., Ring, J., & Olson, R. K. (1999). Training phonological awareness with and without attention to articulation. Journal of Experimental Child Psychology, 72, 271–304.

    Article  Google Scholar 

  • Wise, B. W., Ring, J., & Olson, R. K. (2000). Individual differences in gains from computer-assisted remedial reading with more emphasis on phonological analysis or accurate reading in context. Journal of Experimental Child Psychology, 77, 197–235.

    Article  Google Scholar 

  • Woodcock, R. W. (1989). Woodcock reading mastery tests. Circle Pines, MN: American Guidance Service.

    Google Scholar 

  • Yule, W., Rutter, M., Berger, M., & Thompson, J. (1974). Over- and under-achievement in reading: Distribution in the general population. British Journal of Educational Psychology, 44, 1–12.

    Google Scholar 

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Olson, R.K. Genes, environment, and dyslexia the 2005 Norman Geschwind memorial lecture. Ann. of Dyslexia 56, 205–238 (2006). https://doi.org/10.1007/s11881-006-0010-6

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