Variation in the gene coding for the M5 Muscarinic receptor (CHRM5) influences cigarette dose but is not associated with dependence to drugs of addiction: evidence from a prospective population based cohort study of young adults
2007

Gene Variation and Substance Use in Young Adults

Sample size: 815 publication 10 minutes Evidence: moderate

Author Information

Author(s): Anney Richard JL, Lotfi-Miri Mehrnoush, Olsson Craig A, Reid Sophie C, Hemphill Sheryl A, Patton George C

Primary Institution: Neuropsychiatric Genetics Research Group, Department of Psychiatry, Trinity College Dublin, Dublin, Ireland

Hypothesis

Does variation in the CHRM5 gene influence substance dependence and dosage in young adults?

Conclusion

Variation within the CHRM5 locus may play an important role in tobacco and cannabis use but not in alcohol addiction.

Supporting Evidence

  • Carriers of the rs7162140 T-allele smoked on average 20.1 more cigarettes per week.
  • Carriers of the T-allele had nearly a 3-fold increased risk of developing cannabis dependence.
  • The study is the first to show an association between CHRM5 and substance use in humans.

Takeaway

Some people have a gene that makes them smoke more cigarettes and have a higher chance of being dependent on cannabis.

Methodology

The study screened the CHRM5 gene for polymorphisms and analyzed their association with substance use in a cohort of young adults.

Potential Biases

The analysis was restricted to individuals of European ancestry, which may limit generalizability.

Limitations

The study did not apply correction for multiple testing and had limited power to distinguish between inheritance models.

Participant Demographics

Participants were young adults of European ancestry from Victoria, Australia.

Statistical Information

P-Value

0.01

Confidence Interval

95%CI 1.1-7.4

Statistical Significance

p<0.05

Digital Object Identifier (DOI)

10.1186/1471-2156-8-46

Want to read the original?

Access the complete publication on the publisher's website

View Original Publication