Polymorphisms of the serotonin transporter gene (SERT) have been associated with mental illness. In people with long-term medical conditions, variants of the 5-HTTLPR and STin2 VNTR polymorphisms of SERT have been shown to confer a heightened vulnerability to comorbid depression.
To determine whether the 5-HTTLPR, STin2 VNTR, and rs25531 polymorphisms of SERT are associated with poststroke depression (PSD) in stroke survivors.
A case-control study in which stroke survivors were screened for depressive symptoms and assigned to either a depressed group or a nondepressed group.
Seventy-five stroke survivors with PSD and 75 nondepressed stroke survivors.
Blood or saliva samples were collected from each participant for DNA extraction and genotyping.
Main Outcome Measures
The associations between the 5-HTTLPR, STin2 VNTR, and rs25531 polymorphisms and PSD.
Individuals with the 5-HTTLPR s/s genotype had 3-fold higher odds of PSD compared with l/l or l/xl genotype carriers (odds ratio, 3.1; 95% confidence interval, 1.2-8.3). Participants with the STin2 9/12 or 12/12 genotype had 4-fold higher odds of PSD compared with STin2 10/10 genotype carriers (odds ratio, 4.1; 95% confidence interval, 1.2-13.6). An association of rs25531 with PSD was not shown.
The 5-HTTLPR and the STin2 VNTR, but not the rs25531, polymorphisms of SERT are associated with PSD in stroke survivors. This gives further evidence of a role of SERT polymorphisms in mediating resilience to biopsychosocial stress.