Schizophrenia is thought to have a significant but not solely genetic component. Genetically, schizophrenia and bipolar disorder have much in common, in that the two disorders share a number of the same risk genes. However, the fact is that both illnesses also have some genetic factors that are unique. There are some genetic commonalities with schizophrenia and epilepsy, as well. Environmentally, the risks of developing schizophrenia can even occur before birth. For example, the risk of schizophrenia is increased in individuals whose father is of advanced age or whose mother was malnourished or had one of certain infections during pregnancy. Difficult life circumstances during childhood, like the early loss of a parent, parental poverty, bullying, witnessing domestic violence; being the victim of emotional, sexual, or physical abuse or of physical or emotional neglect; and insecure attachment have been associated with increased risks of developing this illness. Using drugs, particularly marijuana (cannabis), amphetamines, and hallucinogens, has been found to increase the risk of developing schizophrenia. Factors like recent migration, being discriminated against, and how well represented an ethnic group is in a neighborhood can also be a risk or protective factor for developing schizophrenia.