Anxious temperament

An anxious temperament in both humans and monkeys is evident from infanthood, is an important risk factor for later psychopathology, and is known to be heritable. [Editor’s summary]

Behavioural neuroscience: Genes and the anxious brain
Andreas Meyer-Lindenberg
Nature  466, 827–828 (12 August 2010)

Some people are naturally more anxious than others.
A brain-imaging study in monkeys provides surprising insights into which brain regions are under the influence of genes in this phenomenon and which are not.