<span>Numerous human characteristics are known to be controlled by genes. Physical characteristics such as height, hair colour, eye colour and skin colour, and sex (male or female) are all clearly determined by your genetic makeup, however, other human attributes such as intelligence, depression, schizophrenia, or psychopathy are less clearly defined. For each of the latter there is some evidence to suggest a genetic involvement, but the presence or absence of an individual gene or genes is not sufficient by itself to result in the "disease". Environment is known to play a roll. For example, a child may have the genes required to become an orchestra musician, but if music was never encouraged in his/her early life than this innate talent will never be realised.
As for those that are determined by genes. Eye colour, as mentioned, is a clear example. Blue eyes are recessive meaning both parent must have blue eyes in order for the child to have blue eyes. Height operates on similar rules, with two tall parents the likelyhood is that between 75%-100% of the children will be tall, while with one tall and one short parent that drops to more like 50%. This depends on the exact genetic makeup of the parent, i.e. whether they carry one or two genes for being tall.</span>
