Genetic links to ADHD, autism and depression changed with age

By Dr. Liji Thomas, MDReviewed by Lauren HardakerOct 5 2026

A study tracking outcomes from childhood to young adulthood found distinct developmental patterns linking genetic liability for ADHD, autism and depression with peer relationships, suicidality, education and employment.

Study: Investigating the associations between neurodevelopmental and psychiatric genetic liability and adverse social and functional outcomes across childhood, adolescence and young-adulthood. Image credit: BearFotos/Shutterstock.com

A recent study published in the journal Molecular Psychiatry found that genetic liability to neurodevelopmental and psychiatric conditions is associated with a range of social and functional outcomes across development.

Genetics may help explain challenges beyond psychiatric symptoms

Several prevalent mental and neurodevelopmental disorders, such as attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), depression, anxiety, schizophrenia, and bipolar disorder, have some common symptoms and associated illnesses.

They are associated with challenges in social and functional behavior, including impaired social relationships, suicidality, and poorer educational and employment attainment. These issues often lead to healthcare referrals.

However, the role of genetic liability in these associations remains unclear. Despite the demonstrable heritability of neurodevelopmental and psychiatric disorders as well as social and functional outcomes, these have not often been studied in an integrated manner.

The use of polygenic scores (PGS) for neurodevelopmental and psychiatric conditions to examine associations with such outcomes has yielded variable evidence, depending on the stage of life, exposure, and outcome assessed.

Tracking genetic links across three life stages

The study aimed to investigate associations between the PGS for six conditions and social and functional outcomes in three phases of life: childhood, adolescence, and early adulthood.

The conditions were ADHD, ASD, schizophrenia, bipolar disorder, depression, and anxiety. The outcomes comprised peer problems, suicidality, and educational attainment and employment. These capture social functioning and integration, severe loss of well-being, and cognitive-functional development. Moreover, all these domains show changes related to various neurodevelopmental and psychiatric conditions.

The researchers used data from a prospective population-based cohort study, the Avon Longitudinal Study of Parents and Children. The 8,591 participants were unrelated individuals with usable genetic data. Outcomes were assessed at three ages: 10-13, 16, and 24-25 years.

ADHD shows the widest pattern of associations

The ADHD PGS were associated with outcomes across all three evaluation periods, in comparison to ASD PGS and depression PGS, which were more related to outcomes in childhood and in adolescence and young adulthood, respectively.

Overall, the researchers found no strong evidence of associations for schizophrenia, bipolar disorder, or anxiety PGS, although several nominal associations did not survive correction for multiple testing.

Childhood

In childhood, genetic liability to ADHD, ASD, and depression showed associations across several social and functional outcomes.

For peer problems, each standard-deviation increase in ADHD PGS was associated with 13% higher odds, while ASD and depression PGS were associated with 12% and 18% higher odds, respectively. The authors said the ADHD association could reflect shared genetic influences on ADHD and peer problems, or behavioral manifestations of ADHD genetic liability that evoke negative responses from peers.

ADHD and ASD PGS were also associated with childhood suicidality, with 13% and 24% higher odds, respectively, for each standard-deviation increase. However, the two PGS showed contrasting associations with education: ADHD PGS was associated with 40% higher odds of lower educational attainment, whereas ASD PGS was associated with 12% lower odds.

The ASD education finding was more complex than it first appeared. The association with higher educational attainment emerged after accounting for the other PGS and was not clearly present when ASD PGS was examined alone. The authors said this could reflect genetic influences more specific to ASD after accounting for genetic liability shared with ADHD.

Adolescence

By adolescence, the pattern had begun to shift. ADHD PGS remained associated with peer problems, with each standard-deviation increase linked to 21% higher odds. It was also associated with 62% higher odds of lower educational attainment.

Depression PGS became more prominent during this period, with each standard-deviation increase associated with 28% higher odds of suicidality and 39% higher odds of lower educational attainment. In contrast, ASD PGS continued to show the opposite pattern for education, being associated with 23% lower odds of lower educational attainment.

Unlike in childhood, ADHD PGS was not strongly associated with suicidality in adolescence.

Young adulthood

In young adulthood, associations with ADHD and depression PGS dominated the findings.

Both were associated with peer problems, with each standard-deviation increase in ADHD PGS linked to 14% higher odds and depression PGS to 21% higher odds. Depression PGS was also associated with 42% higher odds of suicidality.

The pattern extended to employment and education. ADHD PGS was associated with 29% higher odds of not being in education, employment, or training (NEET), while depression PGS was associated with 26% higher odds.

Taken together, the developmental pattern differed between the two conditions. ADHD PGS showed associations with peer problems and educational or employment outcomes from childhood through young adulthood, while its association with suicidality was confined to childhood. Depression PGS, meanwhile, was associated with childhood peer problems but showed broader associations with education or employment and suicidality from adolescence onward.

This structure also makes the developmental shift from ADHD/ASD toward ADHD/depression much easier for a reader to follow without turning the Results section into a catalog of odds ratios.

Different measures make age comparisons difficult

The study's strengths include its longitudinal design and a general-population sample, which reduces selection bias. Nonetheless, it has several methodological limitations.

Outcome measures were different across developmental stages, limiting comparability. Assessment ages also varied slightly across outcomes. In particular, suicidality was measured differently at each age, and the adolescent measure may have captured a broader phenotype that included some self-harm without suicidal intent.

Although outcomes were collected longitudinally, the statistical analyses examined associations separately at each developmental stage rather than modeling changes within individuals over time. This limited the researchers' ability to determine how associations between neurodevelopmental and psychiatric PGS and social or functional outcomes changed along developmental trajectories.

The genetic databases used for anxiety included only adults, and most participants in the ADHD and ASD genetic databases were children. PGS reflect the cumulative effects of the common genetic variants associated with each condition, while failing to capture the effects of rare mutations.

The power to detect associations varied with the PGS used, which might underlie some null findings for anxiety and ASD.

Genetic links change from childhood to adulthood

“These findings suggest that genetic liability to neurodevelopmental and psychiatric conditions are associated with a range of social/functional outcomes, although the strength and direction of association vary by PGS, outcome and development stage.”

ADHD and depression PGS were each associated with all three outcome domains, but their developmental patterns differed. ADHD PGS showed associations with peer problems and educational attainment or employment across childhood, adolescence and young adulthood, as well as with suicidality in childhood. Depression PGS were associated with educational attainment or employment and suicidality from adolescence onward, while an association with peer problems was also observed in childhood and young adulthood.

In light of these findings, the authors recommend that genetic liability should be assessed for multiple conditions together, keeping in mind the potential for change over the course of development.