Related Experiment Video
Updated: May 28, 2026

Creating Dynamic Images of Short-lived Dopamine Fluctuations with lp-ntPET: Dopamine Movies of Cigarette Smoking
Published on: August 6, 2013
Chromosome 20 shows linkage with DSM-IV nicotine dependence in Finnish adult smokers
Kaisu Keskitalo-Vuokko1, Jenni Hällfors, Ulla Broms
1Corresponding Author: Jaakko Kaprio, M.D., Ph.D., Department of Public Health, University of Helsinki, PO Box 41 (Mannerheimintie 172), Helsinki 00014, Finland.
Introduction:
Chromosome 20 has previously been associated with nicotine dependence (ND) and smoking cessation. Our aim was to replicate and extend these findings.
Methods:
First, a total of 759 subjects belonging to 206 Finnish families were genotyped with 18 microsatellite markers residing on chromosome 20, in order to replicate previous linkage findings. Then, the replication data were combined to an existing whole-genome linkage data resulting in a total of 1,302 genotyped subjects from 357 families. ND diagnosed by DSM-IV criteria, the Fagerström Test for Nicotine Dependence (FTND) score, and the lifetime maximum number of cigarettes smoked within a 24-hr period (MaxCigs24) were used as phenotypes in the nonparametric linkage analyses.
Results:
We replicated previously reported linkage to DSM-IV ND, with a maximum logarithm of odd (LOD) score of 3.8 on 20p11, with females contributing more (maximum LOD [MLOD] score 3.4 on 20q11) than males (MLOD score 2.6 on 20p11). With the combined sample, a suggestive LOD score of 2.3 was observed for DSM-IV ND on 20p11. Sex-specific analyses revealed that the signal was driven by females with a maximum LOD score of 3.3 (on 20q11) versus LOD score of 1.3 in males (on 20q13) in the combined sample. No significant linkage signals were obtained for FTND or MaxCigs24.
Conclusions:
Our results provide further evidence that chromosome 20 harbors genetic variants influencing ND in adult smokers.
Related Concept Videos
Human Genetics
The complex relationship between genetics and psychology is observable through common biological components such...
Drug Dependence
Sex Linked Disorders
Diagnostic and Statistical Manual of Mental Disorders (DSM)
CNS Depressants: Alcohol and Nicotine
Sex-linked Disorders
