Family History and Mental Illness
What the research says. Much of scientific literature seeks to address heritability and genetic links to certain mental health disorders. To start, it is important to understand what is meant by heritable. The Merriam Webster Dictionary defines the word as meaning “the proportion of observed variation in a particular trait (such as height) that can be attributed to inherited genetic factors in contrast to environmental ones” (2022). A 2017 twin study found schizophrenia to be 79% heritable (aligned with findings of previous research), and when expanding illness outcomes to schizophrenia spectrum disorders, the heritability estimate was 73% (Hilker et al., 2017). A study conducted in 2018 explored the potential multigenerational transference of psychiatric disorders, specifically honing in on bipolar disorder; the study found that out of a sample size of nearly 1,000, the illnesses seen in prior generations were associated with the same type of illness in offspring of a …
