Why do people of Chinese/Japanese/Korean origin have the same hair colour?
The Chinese, Japanese and Korean people are all descended from the same racial stock- Chinese. The genes responsible for dark hair and dark eyes is what is known as a dominant gene and by-and-large any offspring will take after the parent with the dominant genes. For example: my girlfriend has black hair and brown eyes (dominant genes) whereas I have blonde hair and blue eyes (recessive or “weaker” genes). Any children we may have will have black hair and brown eyes. In order for us to have blue-eyed children, both of us would need to have the relevant gene. This is how farmers and scientists are able to breed animals which particular traits and is a simple example of genetic engineering. The reason that Europeans as a group have different coloured hair and eyes is because of countless generations of interbreeding, thus the genes are diluted.
