Caspi et al

Question 1

Aim

Answer 1

To determine if there is a gene - environment interaction for the serotonin transporter gene 5-HTT

Question 2

Participants

Answer 2

847 Swedish 26 year olds

Question 3

Procedure

Answer 3

• The participants were split into 3 groups based of their 5-HTT alleles. Group 1 had 2 short alleles, group 2 had 1 short and 1 long allele, and group 3 had 2 long alleles
• The participants then filled out a stressful life events questionnaire and were assessed for depression

Question 4

Results

Answer 4

• Those with one or more short alleles were more likely to experience more symptoms of depression and suicidal ideation in response to stressful life events
• Having the gene alone wasn’t enough to develop symptoms of depression but the gene environment interaction had meant that those with one or more short allele were more likely to develop symptoms of depression in response to stressful life events