A behavior genetic study of self-harm, suicidality, and personality in white and African-American women

Abstract

This study is an examination of genetic and environmental risk leading to suicidal and self-harm behaviors in a representative sample of female young adult twins, and racial differences in the strength of those risk factors. Suicidal and self-harm behaviors proved moderately heritable. They were moderately genetically correlated, and weakly environmentally correlated. Self-harm but not suicide attempts also had unique genetic variance. The personality traits of Neuroticism and Novelty Seeking, as well as internalizing and externalizing diagnoses were genetically correlated with self-harm and suicide attempts. After accounting for genetic influence common to personality, diagnoses, and self-harm or suicide attempts, self-harm but not suicide attempts had unique genetic variance remaining. When examined by race, suicidal behaviors were more common in African American than White women, while self-harm was equally prevalent. The heritability of self-harm and suicide attempts did not vary by race, nor did personality traits or diagnostic status differentially predict them.