Abstract
The expression of many important behavioral outcomes is contingent on passing a developmental milestone, such as puberty, or exposure to an age-dependent risk factor, such as alcohol or drugs. Current models for genetic effects on development have not provided explicit theoretical insight about possible patterns of epistasis and genotype × environment interaction generated by genetic and environmental heterogeneity in the timing of developmental milestones that influence gene expression. We explore theoretically the effects of individual differences in the timing of a developmental milestone on the expression of genetic differences in outcome. The consequences of additive genetic variation and shared environmental variation on timing are examined. Additive genetic effects on timing generate transient epistatic effects on outcome because they modulate the expression of otherwise additive genetic differences in outcome. Epistatic effects will be greatest at ages when there is the most heterogeneity in developmental maturity. Epistasis will gradually disappear as proportionately more individuals mature. Similarly, shared environmental effects on the timing of a milestone will generate transient genotype × shared environment interaction appearing as shared environmental effects on outcome that are greatest when there is the most heterogeneity in developmental maturity. The impact of these effects on age patterns in twin correlations is examined and their relevance to current data on developmental change discussed briefly.
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Baker, L. A., Reynolds, C., and Phelps, E. (1992). Biometrical analysis of individual growth curves. Behav. Genet. 22:253-264.
Brook, J. S., Cohen, P., and Jaeger, L. (1998). Developmental variations in factors related to initial and increased levels of adolescent drug involvement. J. Genet. Psychol. 159:179-194.
Eaves, L. J., and Erkanli, A. (in press). Markov chain Monte Carlo approaches to analysis of genetic and environmental components of human developmental change and G×E interaction. Behav. Genet.
Eaves, L. J., Last, K. A., Martin, N. G., and Jinks, J. L. (1977). A progressive approach to non-additivity and genotype-environmental covariance in the analysis of human differences. Br. J. Math. Statist. Psychol. 30:1-42.
Eaves, L. J., Long, J., and Heath, A. C. (1986). A theory of developmental change in quantitative phenotypes applied to cognitive development. Behav. Genet. 16:143-162.
Eaves, L. J., Martin, N. G., Heath, A. C., Schieken, R., Meyer, J., Silberg, J., Neale, M. C., and Corey, L. (1997). Age changes in the causes of individual differences in conservatism. Behav. Genet. 27:121-124.
Eaves, L. J., Silberg, J. L., and Erkanli, A. (in press). Interaction of genes and life events in the development of depression: A Markov chain Monte Carlo approach. J. Child. Psychol. Psychiatr.
Kandel, D. B., and Chen, K. (2000). Types of marijuana users by longitudinal course. J. Stud. Alcohol. 61:367-378.
Kendler, K. S., Neale, M. C., Sullivan, P., Corey, L. A., Gardner, C. O., and Prescott, C. A. (1999). A population-based twin study in women of smoking initiation and nicotine dependence. Psychol. Med. 29:299-308.
Koopmans, J. R., Slutske, W. S., Heath, A. C., Neale, M. C., and Boomsma, D. I. (1999). The genetics of smoking initiation and quantity smoked in Dutch adolescent and young adult twins. Behav. Genet. 29:383-393.
Meyer, J. M., Eaves, L. J., Heath, A. C., and Martin, N. G. (1991). Estimating genetic influences on the age-at-menarche: A survival analysis approach. Am. J. Med. Genet. 1:148-154.
Neale, M. C., and McArdle, J. J. (2000). Structured latent growth curves for twin data. Twin Res. 3:165-177.
SAS Institute (2000). The SAS Software for Windows for the PC: Version 8. Cary, N. C.: SAS Institute, Inc.
Silberg, J., Rutter, M., and Eaves, L. J. (2001). Genetic and environmental influences on the association between girls' depressive and anxious symptoms in childhood and adolescence. Biol. Psychiatr. Author please supply missing information
Silberg, J. L., Pickles, A., Rutter, M., Hewitt, J. K., Simonoff, E., Maes, H., Carbonneau, R., Murrelle, L., Foley, D. L., and Eaves, L. J. (1999). The influence of genetic factors and life stress on depression in adolescent girls. Arch. Gen. Psychiatr. 56:225-232.
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Eaves, L.J., Silberg, J.L. Modulation of Gene Expression by Genetic and Environmental Heterogeneity in Timing of a Developmental Milestone. Behav Genet 33, 1–6 (2003). https://doi.org/10.1023/A:1021060430942
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DOI: https://doi.org/10.1023/A:1021060430942