Genetic Epidemiology, Translational Neurogenomics, Psychiatric Genetics and Statistical Genetics Laboratories investigate the pattern of disease in families, particularly identical and non-identical twins, to assess the relative importance of genes and environment in a variety of important health problems.
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PMID
11931689
TITLE
Estimating two-stage models for genetic influences on alcohol, tobacco or drug use initiation and dependence vulnerability in twin and family data.
ABSTRACT
Genetic research on risk of alcohol, tobacco or drug dependence must make allowance for the partial overlap of risk-factors for initiation of use, and risk-factors for dependence or other outcomes in users. Except in the extreme cases where genetic and environmental risk-factors for initiation and dependence overlap completely or are uncorrelated, there is no consensus about how best to estimate the magnitude of genetic or environmental correlations between Initiation and Dependence in twin and family data. We explore by computer simulation the biases to estimates of genetic and environmental parameters caused by model misspecification when Initiation can only be defined as a binary variable. For plausible simulated parameter values, the two-stage genetic models that we consider yield estimates of genetic and environmental variances for Dependence that, although biased, are not very discrepant from the true values. However, estimates of genetic (or environmental) correlations between Initiation and Dependence may be seriously biased, and may differ markedly under different two-stage models. Such estimates may have little credibility unless external data favor selection of one particular model. These problems can be avoided if Initiation can be assessed as a multiple-category variable (e.g. never versus early-onset versus later onset user), with at least two categories measurable in users at risk for dependence. Under these conditions, under certain distributional assumptions, recovery of simulated genetic and environmental correlations becomes possible. Illustrative application of the model to Australian twin data on smoking confirmed substantial heritability of smoking persistence (42%) with minimal overlap with genetic influences on initiation.
DATE PUBLISHED
2002 Apr
HISTORY
PUBSTATUS PUBSTATUSDATE
pubmed 2002/04/05 10:00
medline 2002/08/16 10:01
entrez 2002/04/05 10:00
AUTHORS
NAME COLLECTIVENAME LASTNAME FORENAME INITIALS AFFILIATION AFFILIATIONINFO
Heath AC Heath Andrew C AC Department of Psychiatry, Washington University School of Medicine, St Louis, Missouri, USA.
Martin NG Martin Nicholas G NG
Lynskey MT Lynskey Michael T MT
Todorov AA Todorov Alexandre A AA
Madden PA Madden Pamela A F PA
INVESTIGATORS
JOURNAL
VOLUME: 5
ISSUE: 2
TITLE: Twin research : the official journal of the International Society for Twin Studies
ISOABBREVIATION: Twin Res
YEAR: 2002
MONTH: Apr
DAY:
MEDLINEDATE:
SEASON:
CITEDMEDIUM: Print
ISSN: 1369-0523
ISSNTYPE: Print
MEDLINE JOURNAL
MEDLINETA: Twin Res
COUNTRY: Australia
ISSNLINKING: 1369-0523
NLMUNIQUEID: 9815819
PUBLICATION TYPE
PUBLICATIONTYPE TEXT
Journal Article
Research Support, U.S. Gov't, P.H.S.
Review
Twin Study
COMMENTS AND CORRECTIONS
GRANTS
GRANTID AGENCY COUNTRY
P01-CA75581 NCI NIH HHS United States
P50-AA11998 NIAAA NIH HHS United States
R01-AA09022 NIAAA NIH HHS United States
R01-AA10248 NIAAA NIH HHS United States
R01-DA12540 NIDA NIH HHS United States
R01-DA12854 NIDA NIH HHS United States
R37-AA07728 NIAAA NIH HHS United States
GENERAL NOTE
KEYWORDS
MESH HEADINGS
DESCRIPTORNAME QUALIFIERNAME
Australia epidemiology
Cohort Studies epidemiology
Computer Simulation epidemiology
Dependency (Psychology) epidemiology
Diseases in Twins genetics
Environment genetics
Female genetics
Genetic Predisposition to Disease genetics
Humans genetics
Male genetics
Models, Genetic genetics
Multivariate Analysis genetics
Substance-Related Disorders psychology
Twins psychology
SUPPLEMENTARY MESH
GENE SYMBOLS
CHEMICALS
OTHER ID's