GENETIC EXPLANATIONS FOR DEPRESSION

Question 1

Summarise the genetic explanation for depressive disorder

Answer 1

• Depression has a hereditary component (runs in families).
• Studies indicate that first-degree relatives of individuals with depression are 2 or 3x more likely to also develop it, compared to those without a family history.

Question 2

First-degree relatives

Answer 2

• Relatives that share 50% of their DNA.

Question 3

What have twin studies suggested about the concordance rate for depression?

Answer 3

• Identical twins (MZ) have a higher concordance rate for depression than fraternal twins (DZ)

Question 4

What did McGuffin (1996) twin study find?

Answer 4

• Identical (MZ) twins have a (46%) concordance rate for depression compared to (20%) for non-identical (DZ) twins

Question 5

McGuffin et al (1996) methodology?

Answer 5

• Examined 214 twins.
• Where at least one was being treated for depression.