Endophenotype

Endophenotype, also called intermediate phenotype or biological marker, are heritable risk factors correlated with disease liability in affected/unaffected individuals. They’re measured quantitatively through physiological, biochemical, or imaging methods. They’re different from phenotypes, which are observable, but variable characteristics. Examples include: electroencephalographic anomalies, neurocognitive performance deficits, impaired facial emotion recognition, impulsivity, and aggression. The concept of endophenotypes was introduced to psychiatry over 30 years ago by Gottesman and Shields.