Abstract
Age is a potential source of variation that contributes to differences between, but not within, twin pairs. In most genetic analyses of twin data, linear and other functions of age are usually removed prior to model fitting. This correction is typically applied only within twin groups of the same sex and zygosity, and no heterogeneity test of age regressions is performed. Here we include age as a variable in the model-fitting procedure and allow for tests of heterogeneity of age regressions across sex and zygosity groups. The LISREL formulation of the approach is illustrated with data collected from Australian twins on subjective impressions of drunkenness following alcohol consumption. The results indicate significant negative covariation of impressions of drunkenness with age. The data support a simple model of additive genetic and unique environmental variation. No evidence was found for sex differences in genetic or environmental components of variation.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Browne, M. W. (1984). Asymptotically distribution free methods for the analysis of covariance structures.Br. J. Math. Stat. Psychol. 37:62–83.
Cahalan, D., and Room, R. (1974).Problem Drinking Among American Men, Center of Alcohol Studies Monograph No. 6, New Brunswick, N.J.
Cederlöf, R., Friberg, L., and Lundman, T. (1977). The interactions of smoking, environment and heredity and their implications for disease aetiology.Acta Med. Scand. 202(Suppl. 612):1–128.
Clark, W. B., and Midanik, L. (1982). Alcohol use and alcohol problems among U.S. adults: Results of the 1979 national survey. In NIAAA (eds.),Alcohol Consumption and Related Problems, USGPO, Washington, D.C.
Clifford, C. A., Hopper, J. L., Fulker, D. W., and Murray, R. M. (1984). A genetic and environmental analysis of a twin family study of alcohol use, anxiety and depression.Genet. Epidemiol. 1:63–79.
Eaves, L. J., Last, K., Young, P. A., and Martin, N. G. (1978). Model fitting approaches to the analysis of human behaviour.Heredity 41:249–320.
Heath, A. C., and Martin, N. G. (1988). Teenage alcohol use in the Australian twin register: Genetic and social determinants of starting to drink.Alcohol Clin. Exp. Res. (in press).
Heath, A. C., Jardine, R., and Martin, N. G. (1988). Interactive effects of genotype and social environment on female alcohol consumptionJ. Stud. Alcohol (in press).
Heath, A. C., Neale, M. C., Hewitt, J. K., Eaves, L. J., and Fulker, D. W. (1989). Testing structural equation models for twin data using LISREL.Behav. Genet. 19:9–35.
Jardine, R., and Martin, N. G. (1984). Cause of variation in drinking habits in a large twin sample.Acta Genet. Med. Gemellol. 33:435–450.
Jöreskog, K. G., and Sörbom, D. (1986).LISREL: Analysis of Linear Structural Relationships by the Method of Maximum Likelihood, National Educational Resources, Chicago.
Kaprio, J., Koskenvuo, M. D., and Sarna, S. (1981). Cigarette smoking, use of alcohol and leisure time physical activity in same sexed adult twin pairs. InTwin Research 3: Epidemiology & Clinical Studies, A. R. Liss, New York, pp. 37–46.
Kaprio, J., Koskenvuo, M. D., Langinvainio, H., Romanov, K., Sarna, S., and Rose, R. J. (1987). Genetic influences on use and abuse of alcohol: A study of 5638 adult Finnish brothers.Alcohol Clin. Exp. Res. 11:349–356.
Martin, N. G., and Boomsma, D. (1989). Willingness to drive when drunk and personality: A twin study.Behav. Genet. 19:97–111.
Martin, N. G., Eaves, L. J., Kearsey, M. J., and Davies, P. (1978). The power of the classical twin study.Heredity 40:97–111.
Martin, N. G., Oakeshott, J. G., Gibson, J. B., Starmer, G. A., Perl, J., and Wilks, A. V. (1985). A twin study of psychomotor and physiological response to an acute dose of alcohol.Behav. Genet. 15:305–347.
McClearn, G., and Erwin, V. (1982). Mechanisms of genetic influence on alcohol related behaviors. In NIAAA (eds.),Alcohol Consumption and Related Problems, USGPO, Washington, D.C.
McGue, M., and Bouchard, T. (1984). Adjustment of twin data for the effects of age and sex.Behav. Genet 18:325–343.
Mulford, H. A. (1964). Drinking and deviant drinking, USA, 1963.Q. J. Stud. Alcohol 25:634–650.
Neale, M. C., Eaves, L. J., Kendler, K. S., and Hewitt, J. K. (1989). Bias in correlations from selected samples of relatives: The effects of soft selection.Behav. Genet. 19:(in press).
Partanen, J., Bruun, K., and Markkanen, T. (1966).Inheritance of Drinking Behavior: A Study of Intelligence, Personality and Use of Alcohol of Adult Twins, Finnish Foundation for Alcohol Studies, Helsinki.
Riley, J. W., and Marden, C. F. (1947). The social pattern of alcoholic drinking.Q. J. Stud. Alcohol 8:265–273.
Rindskopf, M. (1984). The use of phantom and imaginary latent variables to parameterize constraints in linear structural modelsPsychometrika 49:37–47.
SAS (1985).SAS User's Guide: Basics.Version 5 Edition, SAS Institute Inc., Cary, N.C.
SPSS (1983).SPSS X User's Guide, McGraw-Hill, London.
Vlietinck, R., Derom, R., Neale, M. C., Maes, H. van Loon, H., van Maele, G., Derom, C. and Thiery, M. (1988). Genetic and environmental variation in the birth weight of twins.Behav. Genet. 19:151–161.
Weissman, M. M., Meyers, K., and Harding, P. (1980). Prevalence and psychiatric heterogeneity in a United States urban community.J. Stud. Alcohol 41:672–681.
Author information
Authors and Affiliations
Additional information
The theoretical work and data analysis described in this paper were made possible by NATO Grant 86/0823 and grants from the Belgian National Research Fund, the State University of Gent, and the Catholic University of Leuven. We are also grateful to Drs. R. Vlietinck and R. Derom for excellent organization of the successful workshop. Data collection was made possible by a grant from the Australian Associated Brewers to N.G.M. and Drs. J. G. Oakeshott, J. B. Gibson, and G. A. Starmer and by grants from the Australian National Health and Medical Research Council. The authors were supported by NIH Grants MH-40828 and AA-06781.