Alcohol Research using Australian twins and their families (OZ-ALC)

The Australian twin-family study of alcohol use disorder (OZALC study) derives from telephone diagnostic interview studies of two general population volunteer cohorts of Australian twins (cohort 1, mostly born 1940-1964; cohort 2, born 1964-71) and the spouses of the former cohort - a total of over 11,000 families. Three coordinated studies, using a shared assessment protocol and with a shared goal of gene-discovery, were conducted - one funded by the National Institute on Drug Abuse, the others by the National Institute on Alcoholism and Alcohol Abuse - by investigators associated with the Midwest Alcoholism Research Center at Washington University in St. Louis, and investigators at Queensland Institute of Medical Research, Brisbane, Australia (led by Professor Nicholas Martin), using informative families identified from these cohorts. The first of these (NIDA Nicotine Addiction Genetics [NAG] project, PI Pamela Madden) identified index cases from the 3 cohorts with a history of heavy smoking (smoked 20 or more cigarettes daily, or 40 or more cigarettes on 1 or more occasions) and with additional available full siblings who were smokers, and interviewed and obtained blood samples from twins, and cooperative full siblings and parents, in order to identify families that would be informative for linkage analysis of a quantitative heaviness of smoking trait. The second identified additional families with an index case who either reported a history of alcohol dependence (DSM-IV), or scored above the 85th percentile on a quantitative measure of heaviness of alcohol use (alcohol factor score), derived from measures of frequency of heavy drinking, frequency of drinking to intoxication, and typical weekly consumption in standard drinks (all referenced to the respondent's heaviest drinking period) and of lifetime maximum 1-day alcohol consumption and maximum tolerance to alcohol (drinks before getting drunk or before feeling effects of alcohol). Interview and DNA were obtained from index cases and siblings, and DNA only from available parents. The goal of this second study (NIAAA OZ-ALCOHOL EDAC study, PI Andrew Heath) was to identify sibships including pairs who were either extreme concordant for the quantitative consumption measure (both scoring above the 85th percentile) or extreme discordant (one scoring above the 85th percentile and one scoring below the 30th percentile) that would be informative for linkage analysis. The third identified additional sibships solely on the basis of large sibship size, regardless of alcohol or tobacco use phenotypes (NIAAA OZ-BIGSIB study, PIs the late Richard Todd, Andrew Heath). From these coordinated studies a case-control series of alcohol dependent individuals and unaffected controls were constructed for a family-based Genomewide Association Study (OZALC-GWAS) of heaviness of alcohol use and alcohol dependence, funded by the National Institute of Alcoholism and Alcohol Abuse. These data are made available here for all investigators studying outcomes related to alcohol or tobacco use (including major depressive disorder).]]>
TOBACCO AND ALCOHOL STUDY RESPONDENT BOOKLET: VERSION FOR BROTHERS AND SISTERSNicotine Addiction Genetics (NAG) Interview version 1/27/03Family-based sampling design with presence or absence of history of alcohol dependence used to define case versus control status.]]>
1979-1981 Australian Alcohol Challenge Twin Study (subsample of cohort 1 twins, N=412) 1980-1982 Australian Twin Cohort 1 Questionnaire mailing 1988-1990 Australian Twin Cohort 1 Questionnaire follow-up 1988-1990 Australian Twin Cohort 2 Questionnaire mailing 1992-1993 Australian Twin Cohort 1 Diagnostic Interview Survey, Phase 1 1994-1996 Australian Twin Cohort 1 Diagnostic Interview Survey, Phase 2 1994-1997 Diagnostic Interview Survey of Spouses of Cohort 1 Twins 1996-2000 Australian Twin Cohort 2 Diagnostic Interview Survey 2000-2006 Nicotine Addiction Genetics study, data-collection and linkage phase 2001-2008 OZALC-EDAC study, data-collection and genotyping phase 2001-2009 OZALC-BIGSIB study, data-collection and genotyping phase 01/2008 Approval for GWAS genotyping by CIDR 2009 GWAS data released by CIDR ]]>