It's partially environmental, and therefore can be socially correlated. We know of many conditions that are caused by changes in pre-natal environment (e.g. folic acid deficiency in the mother causes neural tube defects). Genes you don't get to pick, but everything that happens after fertilization is absolutely impacted by the external environment in many ways.
The ongoing debate is culture versus biology, with genes being the focus on the biological side. The prenatal environment isn't cultural, although some cultural factors can play a role in the mother's health. Biological factors are always mixed in with the environment, but that doesn't mean the environment in terms of human culture is 100% the determining factor for behavior.
