Birmaher B, Hafeman D, Merranko J, et al. - Given the relevance of establishing genetic contributions to the transmission of bipolar disorder (BD) from parents to offspring for ascertaining the risk of developing this disorder and validating BD in youth, researchers herein examined if bipolar disorder (BD) polygenic risk score (PRS) is specifically associated with the familial transmission of BD in youth.

• A case-control study including parents with BD I/II and their offspring and parents without BD (healthy or non-BD psychopathology) and their offspring.

• A total of 336 parents and 409 offspring were studied.

• BD PRS was significantly and specifically higher for those with mood disorders than those without BD.

• Risk for offspring to develop BD was recorded to be increased in correlation with parental and offspring BD PRS, beyond the associations of parental BD diagnosis.

• Overall, BD offspring specifically show higher BD PRS which may add to the clinical validation of BD in youth and increases the risk for BD; however, the BD PRS has small association, due to which it cannot be used alone to estimate the risk to develop BD.