To what extent does genetic inheritance influence behaviour?

Refer to the paper 1 section B assessment criteria when awarding marks.

The command term “to what extent” requires candidates to consider the merits of the principle that genetic inheritance influences behaviour.

Candidates may choose a single behaviour (such as intelligence, depression or obesity), or they may choose a number of behaviours and take a more holistic approach.

In order to address the command term “to what extent”, candidates may address:

• the interaction of genes with the environment
• strengths and limitations of genetic research
• alternative explanations – i.e. cognitive and sociocultural explanations.

Examples of relevant studies include, but are not limited to:

• Heston’s (1966), Gottesman’s (1991) and Kety et al.’s (1975) studies examining the genetic inheritance of schizophrenia
• Kendler et al. (2006), Caspi et al. (2003) and Nurnberger and Gershon (1982) on the possible genetic factors involved in depression
• Garn et al. (1981) and Stunkard et al. (1990) examining obesity and genetic factors
• Bouchard et al. (1990), Scarr and Weinberg (1977), and Plomin and Petrill (1977) examining IQ and genetic inheritance.

Explanations of the role of genetic inheritance may refer to concordance rates, specific research regarding the properties of specific genes, or findings from twin and adoption studies. If a candidate makes reference to research from evolutionary psychology, the focus of the response must be on how genetic inheritance influences the behaviour.