Valerie Knopik, PhD, is director of the Division of Behavioral Genetics in the department of psychiatry at Rhode Island Hospital. Her primary area of interest is the joint effects and interaction of genetic and environmental (specifically prenatal and early postnatal) risk factors on childhood externalizing behavior (for example, attention deficit hyperactivity disorder [ADHD], conduct disorder, oppositional defiant disorder), and associated learning and cognitive deficits. She received her doctoral degree in psychology and behavioral genetics from the Institute for Behavioral Genetics and the University of Colorado, and completed a postdoctoral fellowship in psychiatric genetics and genetic epidemiology at Washington University School of Medicine in St. Louis, Missouri.
Knopik's primary research is funded by the National Institute on Drug Abuse (NIDA) and focuses on the effects of prenatal tobacco exposure and genetics on neuropsychological outcomes and ADHD. She is also involved as a co-investigator in a number of research grants from NIDA, the National Institute on Alcohol Abuse and Alcoholism, and the National Institute of Mental Health to support research on genetic effects on a range of outcomes such as cannabis dependence, sleep, and alcohol use disorder. She has received numerous honors and awards for her research, including a NIDA Genetics Workgroup Sponsorship Award and the Behavior Genetics Association Fuller and Scott Early Career Award.
Knopik, V.S., DeFries, J.C., and Alarcón, M. (1996). Gender differences in cognitive abilities of opposite-sex and same-sex twin pairs with reading disability. Annals of Dyslexia 46, 241-257.
Knopik, V.S., Alarcón, M., and DeFries, J.C. (1997). Comorbidity of mathematics and reading deficits: Evidence for a genetic etiology. Behavior Genetics 27(5), 447-453.
Knopik, V.S., Alarcón, M., and DeFries, J.C., (1998). Common and specific gender influences on individual differences in reading performance: A twin study. Personality and Individual Differences 25 269-277.
Knopik, V.S. and DeFries, J.C. (1998). A twin study of gender-influenced individual differences in general cognitive ability. Intelligence 26(2), 81-89.
Knopik, V.S. and DeFries, J.C. (1999). Etiology of covariation between reading and mathematics performance: A twin study. Twin Research 2, 226-234.
Alarcón, M., Knopik, V.S., and DeFries, J.C. (2000). Covariation of mathematics achievement and general cognitive ability. Journal of School Psychology 38(1), 63-77.
Davis, C.J., Knopik, V.S., Wadsworth, S.J., and DeFries, J.C. (2000). Self-reported reading problems in parents of twins with and without reading difficulties. Twin Research 3(2), 88-91.
Wadsworth, S.J., Knopik, V.S., and DeFries, J.C. (2000). Reading disability in boys and girls: No evidence for a differential genetic etiology. Reading and Writing: An Interdisciplinary Journal, 13 133-145.
Davis, C.J., Knopik, V.S., Olson, R.K., Wadsworth, S.J., and DeFries, J.C. (2001). Genetic and environmental influences on rapid naming and reading ability: A twin study. Annals of Dyslexia 51, 231-247.
Davis, C.J., Gayán, J., Knopik, V.S., Smith, S.D., Cardon, L.R., Pennington, B.F., Olson, R.K., and DeFries, J.C. (2001). Etiology of reading difficulties and rapid naming: The Colorado Twin Study. Behavior Genetics 31(6), 625-635.
Willcutt, E.G., Pennington, B.F., Smith, S.D., Cardon, L.R., Gayán, J., Knopik, V.S., Olson, R.K., and DeFries, J.C. (2002). Quantitative trait locus for reading disability on chromosome 6p is pleiotropic for attention-deficit/hyperactivity disorder. Neuropsychiatric Genetics 114, 260-268.
Knopik, V.S., Smith, S.D., Cardon, L.R., Pennington, B.F., Gayán, J., Olson, R.K., and DeFries, J.C. (2002). Differential genetic etiology of reading component processes as a function of IQ. Behavioral Genetics 32(3), 181-198.
Heath, A.C., Knopik, V.S., Madden, P.A.F., Neuman, R.J., Lynskey, M.J., Slutske, W.S., Jacob, T., and Martin, N.G. (2003). Accuracy of mothers' retrospective reports of smoking during pregnancy: Comparison with twin sister informant ratings. Twin Research 6(4), 297-301.
Nelson, E.C., Heath A.C., Bucholz, K.K., Madden, P.A.F., Fu, Q., Knopik, V.S., Lynskey, M.T., Whitfield, J.B., Statham, D.J., and Martin, N.G. (2004). The genetic epidemiology of alcoholic blackouts. Archives of General Psychiatry 61(3), 257-263.
Knopik, V.S., Heath, A.C., Madden, P.A.F., Bucholz, K.K., Slutske, W.S., Nelson, E.C., Statham, D., Whitfield, J.B., and Martin, N.G. (2004). Genetic effects on alcohol dependence risk: Re-evaluating the importance of psychiatric and other heritable risk factors. Psychological Medicine 34, 1519-1530.
Romeis, J.C., Grant, J.D., Knopik, V.S., Pederson, N.L., and Heath, A.C. (2004). The genetics of middle-age spread in middle-class males. Twin Research and Human Genetics, 7(6), 596-602.
Knopik, V.S., Sparrow, E.P., Madden, P.A.F., Bucholz, K.K., Hudziak, J.J., Reich W., Slutske, W.S., Grant, J.D., McLaughlin, T.L., Todorov, A., Todd, R.D., and Heath, A.C. (2005). Contributions of parental alcoholism, prenatal substance exposure, and genetic transmission to child ADHD risk: A female twin study. Psychological Medicine 35(5), 625-635.
Lynskey, M.T., Nelson, E.C., Neuman, R., Bucholz, K.K., Madden, P.A.F., Knopik, V.S., Slutske, W., Whitfield, J., Martin, N.G., Heath, A.C. (2005). Limitations of DSM-IV operationalizations of alcohol abuse and dependence in a sample of Australian twins. Twin Research and Human Genetics 8(6), 574-584.
Knopik, V.S., Heath, A.C., Jacob, T., Slutske, W.S., Bucholz, K.K., Madden, P.A.F., Waldron, M., Martin, N.G. (2006). Maternal alcohol use disorder and offspring ADHD: Disentangling genetic and environmental effects using a children-of-twins design. Psychological Medicine 36(10), 1461-1472.
Ray, L. Rhee, S.H., Stallings, M.C., Knopik, V.S., Hutchison, K.E. (2007). Examining the heritability of tension reduction after cigarette smoking: Results from an experimental twin study. Twin Research and Human Genetics 10, 546-553.
Agrawal, A., Knopik, V.S., Pergadia, M.L., Waldron, M., Bucholz, K.K., Martin, N.G., Madden, P.A.F., Heath, A.C. (2008). Evaluating measured correlates of cigarette smoking during pregnancy and its genetic and environmental overlap with smoking progression. Nicotine and Tobacco Research 10(4), 567-78.
Knopik, V.S. (2009). Maternal smoking during pregnancy and child outcomes: Real or spurious effect? Developmental Neuropsychology 34, 1-36.
Knopik, V.S., Jacob, T., Haber, R., Swenson, L.P., Howell, D. (2009a). Paternal alcoholism and offspring ADHD problems: A children-of-twins design. Twin Research and Human Genetics 12(1), 53-62.
Knopik, V.S., Heath, A.C., Bucholz, K.K., Madden, P.A.F., Waldron, M. (2009b; E-Pub ahead of print). Genetic and environmental influences on externalizing behavior and alcohol problems in adolescence: A female twin study. Pharmacology, Biochemistry, and Behavior. DOI information: 10.1016/j.pbb.2009.03.011
Esposito-Smythers, C., Spirito, A., Rizzo, C., McGeary, J.E., Knopik, V.S. (2009; E-Pub ahead of print). Associations of the DRD2 TaqIA polymorphism with impulsivity and substance use: Preliminary results from a clinical sample of adolescents. Pharmacology, Biochemistry, and Behavior. DOI information: 10.1016/j.pbb.2009.03.012
Miranda Jr., R., Ray, L., Justus, A., Meyerson, L.A., Knopik, V.S., McGeary, J., Monti, P.M. (in press). Initial evidence of an association between OPRM1 and adolescent alcohol misuse. Alcoholism: Clinical and Experimental Research
DeFries, J.C., Knopik, V.S., and Wadsworth, S.J. (1999). Colorado Twin Study of Reading Disability. In D.D. Duane (Ed.), Reading and attention disorder: Neurobiological correlates (pp. 17-41). Baltimore, Maryland: York Press.
Wadsworth, S.J., Davis, C.J., Knopik, V.S., Willcutt, E.G., and DeFries, J.C. (2002). Genetics of reading disabilities. In I. Arcolini and G. Zardini (Eds.) I disturbi di apprendimento della lettura e della scittura (p.23-35). Milan, Italy: FrancoAngeli.