Scientists Developed a Heritable Alcohol Consumption Measure That Also Correlated With Cannabis Use

A single-factor alcohol consumption score combining four measures was 50% heritable and correlated with both nicotine and cannabis use, making it useful for gene-mapping studies.

Agrawal, Arpana et al.·Journal of studies on alcohol and drugs·2009·Moderate EvidenceCross-Sectional
RTHC-00340Cross SectionalModerate Evidence2009RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
N=489

What This Study Found

Researchers developed a quantitative alcohol consumption factor score using four measures: maximum typical consumption, maximum drinks in 24 hours, frequency of 5+ drinks per day, and frequency of intoxication.

The composite score showed good psychometric properties: factor loadings of 0.60-0.90, measurement invariance across two samples and genders, and 50% heritability. Individual component measures were 34-47% heritable.

Importantly for substance use research, the alcohol factor correlated with nicotine and cannabis use measures similarly across samples and genders, supporting construct validity and suggesting shared genetic influences across substances.

The genetic variance in the composite factor accounted for a majority of the genetic variance in each individual measure, meaning the factor captured the common genetic influence underlying different aspects of alcohol consumption.

Key Numbers

3,787 female twins + 489 college sample. Factor loadings: 0.60-0.90. Heritability of composite score: 50%. Individual measures: 34-47% heritable. Correlated with nicotine and cannabis use.

How They Did This

Twin study using 3,787 young adult twin women and 489 men and women from a college drinking study. Factor analysis, measurement invariance testing, construct validation against tobacco/cannabis use, and genetic psychometric modeling were performed.

Why This Research Matters

Better measurement tools for substance use improve the ability to identify genetic variants. The correlation with cannabis use supported the idea of shared genetic vulnerability across substances.

The Bigger Picture

Developing reliable, heritable phenotypes is essential for gene-mapping studies. This measure has been used in subsequent GWAS and has helped identify genetic variants for alcohol consumption.

What This Study Doesn't Tell Us

The primary sample was all female. Cross-validation with the college sample was helpful but limited in size. Cannabis use was examined as a correlate, not as the primary focus.

Questions This Raises

  • ?Can similar factor scores be developed for cannabis consumption specifically?
  • ?Would the genetic overlap between alcohol and cannabis consumption measures help identify shared vulnerability genes?

Trust & Context

Key Stat:
50% heritable alcohol consumption factor correlated with cannabis and nicotine use
Evidence Grade:
This is a well-designed twin study with rigorous psychometric validation, providing moderate evidence for the measure's utility and the shared genetics of substance use.
Study Age:
Published in 2009. This type of phenotype development has been essential for the GWAS era and subsequent identification of specific genetic variants.
Original Title:
Developing a quantitative measure of alcohol consumption for genomic studies on prospective cohorts.
Published In:
Journal of studies on alcohol and drugs, 70(2), 157-68 (2009)
Database ID:
RTHC-00340

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Why does an alcohol measure matter for cannabis research?

The finding that the alcohol consumption measure correlated with cannabis use suggests shared genetic vulnerability. Identifying genes through alcohol consumption measures may also reveal genes relevant to cannabis use and general addiction.

What does 50% heritable mean?

It means that about half of the variation in alcohol consumption patterns in the population can be attributed to genetic differences. The other half is due to environmental factors like peer influence, availability, and life experiences.

Read More on RethinkTHC

Cite This Study

RTHC-00340·https://rethinkthc.com/research/RTHC-00340

APA

Agrawal, Arpana; Grant, Julia D; Littlefield, Andrew; Waldron, Mary; Pergadia, Michele L; Lynskey, Michael T; Madden, Pamela A F; Todorov, Alexandre; Trull, Timothy; Bucholz, Kathleen K; Todd, Richard D; Sher, Kenneth; Heath, Andrew C. (2009). Developing a quantitative measure of alcohol consumption for genomic studies on prospective cohorts.. Journal of studies on alcohol and drugs, 70(2), 157-68.

MLA

Agrawal, Arpana, et al. "Developing a quantitative measure of alcohol consumption for genomic studies on prospective cohorts.." Journal of studies on alcohol and drugs, 2009.

RethinkTHC

RethinkTHC Research Database. "Developing a quantitative measure of alcohol consumption for..." RTHC-00340. Retrieved from https://rethinkthc.com/research/agrawal-2009-developing-a-quantitative-measure

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.