What did Groothorst et al. conclude about OCD heritability in children compared with adults?

What did Groothorst et al. conclude about OCD heritability in children compared with adults?

• A. Inheritance is higher in children (roughly 45-65%) than in adults (roughly 27-47%)
• B. Inheritance is higher in adults
• C. Inheritance is negligible in both
• D. Inheritance is identical across ages

Answer: (A)

The idea being tested is how much genetics contribute to OCD at different ages, i.e., the heritability of OCD in children versus adults. Groothorst and colleagues used twin studies to compare genetic influence across these groups and found that genetic factors account for a larger share of OCD variation in children—roughly 45–65%—compared with adults, where the estimate is about 27–47%. This means OCD in childhood has a stronger genetic component, while environmental or non-genetic factors play a relatively bigger role as people age. The other possibilities aren’t supported because the data show higher heritability in children, not adults; it isn’t negligible; and it isn’t identical across ages.

The idea being tested is how much genetics contribute to OCD at different ages, i.e., the heritability of OCD in children versus adults. Groothorst and colleagues used twin studies to compare genetic influence across these groups and found that genetic factors account for a larger share of OCD variation in children—roughly 45–65%—compared with adults, where the estimate is about 27–47%. This means OCD in childhood has a stronger genetic component, while environmental or non-genetic factors play a relatively bigger role as people age. The other possibilities aren’t supported because the data show higher heritability in children, not adults; it isn’t negligible; and it isn’t identical across ages.