Year: 1997 Source: The Psychiatric Clinics of North America, v.20, no.3, (September 1997), p.595-611 SIEC No: 19980522

Clinical studies show that a family history of suicide is associated with an increased risk of both attempted & completed suicide. Twin studies show that monozygotic twins have a greater concordance for suicidal behaviour than dizygotic twins. Adoption studies also suggest that there may be genetic factors in suicide. Most recently, molecular genetic studies report that polymorphisms of the tryptophan hydroxylase gene are associated with suicidal behaviour. (47 refs.)