Commentary
Generally a strong study, addressing some common "correlation != causation" responses
Children with a higher genetic propensity for ADHD were significantly more likely to be followed by their parents separating. The effect held even after accounting for the parents’ own genetics. It was not simply that ADHD traits run in families and parents with ADHD genes are also more likely to split up. When the researchers statistically removed the parents’ genetic contribution, the child’s own genetic profile still predicted parental separation independently.
Hard to evaluate if that result came from p-hacking though
The finding that emerged was specific. Across traits including educational attainment, cognitive ability, conscientiousness, and neuroticism, the children’s genetic propensities showed limited ability to predict what happened to the parents. The exception was ADHD. A one standard deviation increase in the child’s ADHD polygenic index was associated with a 7% higher likelihood of parental separation in the years following the child’s birth.