Genome-wide association studies on human behavioural traits are producing large amounts
of polygenic signals with significant predictive power and potentially useful biological clues.
Behavioural traits are more distal and are less directly under biological control compared
with physical characteristics, which makes the associated genetic effects harder to interpret.
The results of genome-wide association studies for human behaviour are likely made up of a
composite of signals from different sources. While sample sizes continue to increase, we …