Behavior Genetics

, Volume 33, Issue 3, pp 247–255 | Cite as

ADHD: Sibling Interaction or Dominance: An Evaluation of Statistical Power

  • M. J. H. Rietveld
  • D. Posthuma
  • C. V. Dolan
  • D. I. Boomsma
Article

Abstract

Sibling interaction effects are suggested by a difference in phenotypic variance between mono-zygotic (MZ) twins and dizygotic (DZ) twins, and a pattern of twin correlations that is inconsistent with additive genetic influences. Notably, negative sibling interaction will result in MZ correlations which are more than twice as high as DZ correlations, a pattern also seen in the presence of genetic dominance. Negative sibling interaction effects have been reported in most genetic studies on Attention Deficit Hyperactivity Disorder (ADHD) and related phenotypes, while the presence of genetic dominance is not always considered in these studies. In the present paper the statistical power to detect both negative sibling interaction effects and genetic dominance is explored. Power calculations are presented for univariate models including sources of variation due to additive genetic influences, unique environmental influences, dominant genetic influences and a negative sibling interaction (i.e., contrast effect) between phenotypes of twins. Parameter values for heritability and contrast effects are chosen in accordance with published behavior genetic studies on ADHD and associated phenotypes. Results show that when both genetic dominance and contrast effects are truly present and using a classical twin design, genetic dominance is more likely to go undetected than the contrast effect. Failure to detect the presence of genetic dominance consequently gives rise to slightly biased estimates of additive genetic effects, unique environmental effects, and the contrast effect. Contrast effects are more easily detected in the absence of genetic dominance. If the significance of the contrast effect is evaluated while also including genetic dominance, small contrast effects are likely to go undetected, resulting in a relatively large bias in estimates of the other parameters. Alternative genetic designs, such as adding pairs of unrelated siblings reared together to a classical twin design, or adding non-twin siblings to twin pairs, greatly enhances the statistical power to detect contrast effects as well as the power to distinguish between genetic dominance and contrast effects.

Statistical power sibling interaction genetic dominance ADHD power calculation twin study heritability 

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References

  1. Abramovitch, R., Carter, C., and Lando, B. (1979). Sibling interaction in the home. Child Dev. 50: 997-1003.Google Scholar
  2. Achenbach, T. M. (1991). Manual for the child behavior checklist/4–18. Burlington, VT: University of Vermont, Department of Psychiatry.Google Scholar
  3. Bekker, P. A., Merckens, A., and Wansbeek, T. J. (1993). Identification, equivalent models, and computer algebra. Burlington, VT: Academic Press.Google Scholar
  4. Boomsma, D. I. (1998). Twin registers in Europe: An overview. Twin Res. 1: 34-51.Google Scholar
  5. Carey, G. (1986). Sibling imitation and contrast effects. Behav. Genet. 16: 319-341.Google Scholar
  6. Carey, G. (1992). Twin imitation for antisocial behavior: Implications for genetic and family environment research. J. Abnorm. Psychol. 101: 18-25.Google Scholar
  7. Eaves, L. J. (1972). Computer simulation of sample size and experimental design in human psychogenetics. Psychol. Bull. 77: 144-152.Google Scholar
  8. Eaves, L. J. (1976). A model for sibling effects in man. Heredity 36: 205-214.Google Scholar
  9. Eaves, L. J., Rutter, M., Silberg, J. L., Shillady, L., Maes, H., and Pickles, A. (2000). Genetic and environmental causes of covariation in interview assessments of disruptive behavior in child and adolescent twins. Behav. Genet. 30: 321-334.Google Scholar
  10. Eaves, L. J., Silberg, J. L., Maes, H. H., Simonoff, E., Pickles, A., Rutter, M., Neale, M. C., Reynolds, C. A., Erikson, M. T., Heath, A. C., Loeber, R., Truett, K. R., and Hewitt, J. K. (1997). Genetics and developmental psychopathology: 2. The main effects of genes and environment on behavioral problems in the Virginia Twin Study of Adolescent Behavioral Development. J. Child Psychol. Psychiatry 38: 965-980.Google Scholar
  11. Garcia, M. M., Shaw, D. S., Winslow, E. B., and Yaggi, K. E. (2000). Destructive sibling conflict and the development of conduct problems in young boys. Dev. Psychol. 36: 44-53.Google Scholar
  12. Gjone, H., Stevenson, J., and Sundet, J. M. (1996). Genetic influence on parent-reported attention-related problems in a Norwegian general population twin sample. J. Am. Acad. Child Adolesc. Psychiatry 35: 588-596.Google Scholar
  13. Heck, A. (1997). Introduction to MAPLE (2nd ed.). New York: Springer-Verlag.Google Scholar
  14. Hewitt, J. K., and Heath, A. C. (1988). A note on computing the chisquare noncentrality parameter for power analyses. Behav. Genet. 18: 105-108.Google Scholar
  15. Hudziak, J. J., Rudiger, L. P., Neale, M. C., Heath, A. C., and Todd, R. D. (2000). A twin study of inattentive, aggressive and anxious/depressed behaviors. J. Am. Acad. Child Adolesc. Psychiatry 39: 469-476.Google Scholar
  16. Kenny, D. A. (1979). Correlation and causality. New York: Wiley.Google Scholar
  17. Kuntsi, J., Gayán, J., and Stevenson, J. (2000). Parents' and teachers' ratings of problem behaviours in children: genetic and contrast effects. Twin Res. 3: 251-258.Google Scholar
  18. Levy, F., Hay, D. A., McStephen, M., Wood, C., and Waldman, I. (1997). Attention-deficit hyperactivity disorder. A category or a continuum? Genetic analysis of a large-scale twin study. J. Am. Acad. Child Adolesc. Psychiatry 36: 737-744.Google Scholar
  19. Martin, N. G., Eaves, L. J., Kearsey, M. J., and Davies, P. (1978). The power of the classical twin study. Heredity 40: 97-116.Google Scholar
  20. Martin, N., Scourfield, J., and McGuffin, P. (2002). Observer effects and heritability of childhood attention-deficit hyperactivity disorder symptoms. Br. J. Psychiatry 180: 260-265.Google Scholar
  21. Nadder, T. S., Silberg, J. L., Eaves, L. J., Maes, H. H., and Meyer, J. M. (1998). Genetic effects on ADHD symptomatology in 7-to 13-year-old twins: Results from a telephone survey. Behav. Genet. 28: 83-100.Google Scholar
  22. Nadder, T. S., Silberg, J. L., Rutter, M., Maes, H. H., and Eaves, L. J. (2001). Comparison of multiple measures of ADHD symptomatology: A multivariate genetic analysis. J. Child Psychol. Psychiatry 42: 475-486.Google Scholar
  23. Neale, M. C., Boker, S. M., Xie, G., and Maes, H. H. (1999). Mx: Statistical Modeling. Box 126 MCV, Richmond, VA 23298: Department of Psychiatry. 5th ed.Google Scholar
  24. Neale, M. C., and Cardon, L. R. (1992). Methodology for genetic studies of twins and families. Dordrecht Boston: Kluwer Academic Publishers.Google Scholar
  25. Neale, M. C., and Stevenson, J. (1989). Rater bias in the EASI Temperament Scales: A twin study. J. Pers. Soc. Psychol. 56: 446-455.Google Scholar
  26. Patterson, G. R. (1984). Siblings: Fellow travelers in coercive family processes. In: Blanchard, R. J. (ed.). Advances in the study of aggression, pp. 174-213. New York: Academic Press.Google Scholar
  27. Posthuma, D., and Boomsma, D. I. (2000). A note on the statistical power in extended twin designs. Behav. Genet. 30: 147-158.Google Scholar
  28. Price, T. S., Simonoff, E., Waldman, I., Asherson, P., Curran, S., and Plomin, R. What is stable about hyperactive behaviors in preschool children is genetic: Implications for molecular genetic studies. Submitted.Google Scholar
  29. Rhee, S. H., Waldman, I. D., Hay, D. A., and Levy, F. (1999). Sex differences in genetic and environmental influences on DSMIII-R Attention-Deficit/Hyperactivity Disorder. J. Abnorm. Psychol. 108: 24-41.Google Scholar
  30. Rietveld, M. J. H., Hudziak, J. J., Bartels, M., van Beijsterveldt, G. C. M., and Boomsma, D. I. (2003) Heritability of attention problems in children: I. Cross-sectional results from age 3 to 12. Neuropsychiat. Genet. 1176: 102-113.Google Scholar
  31. Rowe, D. C., Rodgers, J. L., and Meseck-Bushey, S. (1992). Sibling delinquency and the family environment: Shared and unshared influences. Child Dev. 63: 59-67.Google Scholar
  32. Saudino, K. J., Cherny, S. S., and Plomin, R. (2000). Parent ratings of temperament in twins: explaining the ‘too low’ DZ correlations. Twin Res. 3: 224-233.Google Scholar
  33. Schmitz, S., Cherny, S. S., and Fulker, D. W. (1998). Increase in power through multivariate analyses. Behav. Genet. 28: 357-364.Google Scholar
  34. Schmitz, S., Fulker, D. W., and Mrazek, D. A. (1995). Problem behavior in early and middle childhood: An initial behavior genetic analysis. J. Child Psychol. Psychiatry 36: 1443-1458.Google Scholar
  35. Segal, N. (2000). Virtual twins: new findings on within-family environmental influences on intelligence. J. Edu. Psychol. 92: 442-448.Google Scholar
  36. Sherman, D. K., Iacono, W. G., and McGue, M. K. (1997). Attention-deficit hyperactivity disorder dimensions. A twin study of inattention and impulsivity-hyperactivity. J. Am. Acad. Child Adolesc. Psychiatry 36: 745-753.Google Scholar
  37. Simonoff, E., Pickles, A., Hervas, A., Silberg, J. L., Rutter, M., and Eaves, L. (1998). Genetic influences on childhood hyperactivity: Contrast effects imply parental rating bias, not sibling interaction. Psychol. Med. 28: 825-837.Google Scholar
  38. Spinath, F. M., and Angleitner, A. (1998). Contrast effects in Buss and Plomin's EAS questionnaire: a behavioral-genetic study on early developing personality traits assessed through parental ratings. Pers. Individ. Diff. 25: 947-963.Google Scholar
  39. Stevenson, J. (1992). Evidence for a genetic etiology in hyperactivity in children. Behav. Genet. 22: 337-344.Google Scholar
  40. Thapar, A., Harrington, R., Ross, K., and McGuffin, P. (2000). Does the definition of ADHD affect heritability? J. Am. Acad. Child Adolesc. Psychiatry 39: 1528-1536.Google Scholar
  41. Thapar, A., Hervas, A., and McGuffin, P. (1995). Childhood hyperactivity scores are highly heritable and show sibling competition effects: Twin study evidence. Behav. Genet. 25: 537-544.Google Scholar
  42. Van Beijsterveldt, C. E. M., Verhulst, F. C., Molenaar, P. C. M., and Boomsma, D. I. (submitted). The genetic basis of problem behavior in 5-year-old Dutch twin pairs.Google Scholar

Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  • M. J. H. Rietveld
  • D. Posthuma
  • C. V. Dolan
  • D. I. Boomsma

There are no affiliations available

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