Which of the following research methods are designed to investigate the relative importance of genetic and environmental factors that contribute to developing medical disorders?

Question

Quizplus · Accepted Answer

All three methods (studies of identical twins and fraternal twins, studies of identical twins reared apart, and studies of adopted children) are used to investigate the relative importance of genetic and environmental factors in the development of medical disorders. Identical twins and fraternal twins can reveal whether a disorder has a genetic component by comparing the rates of the disorder between the two types of twins. Studies of identical twins reared apart can further disentangle the effects of genetics and environment by comparing the rates of the disorder between twins who share identical genes but different environments. Studies of adopted children can also help disentangle the effects of genetics and environment by comparing the rates of the disorder between biological relatives (who share genetics but not typically environments) and adopted relatives (who share environment but not typically genetics).

Which of the Following Research Methods Are Designed to Investigate