Genes study: Kendler

Question 1

What was the aim of this study?

Answer 1

To investigate the genetic and environmental factors that contribute to major depressive disorder

Question 2

What was the procedure of this study?

Answer 2

• 42,000 twins interviewed on major lifetime depression by a criteria
• Used data from the Swedish Twin registry
• Large sample of both identical and non identical twins
• Diagnostic interviews and clinical assessments to determine whether depression occurred

Question 3

What were the findings?

Answer 3

Major depression has a significant genetic influence
Higher concordance rate for depression in identical twins compared to non identical twins
However environmental factors also played a role in depression

Question 4

What was the conclusion?

Answer 4

While genetics contributed to the development of the disorder environmental factors (.i.e. life stressors etc) also played a significant role