When most people think about the genetics of polycystic ovary syndrome (PCOS), they naturally focus on maternal inheritance. After all, PCOS is a condition that affects women, so the assumption is that risk is passed down primarily through mothers.. But a growing body of research suggests that fathers also play a significant role in the heritability of PCOS — and their health may influence their daughters’ risk in unexpected ways. In this article, part two of our Multi‑Part PCOS Genetics & Origins Series, we explore:
- How PCOS may be inherited from the father
- Evidence linking paternal metabolic or cardiovascular disease to daughters’ PCOS risk
- How male relatives themselves may exhibit PCOS‑related traits
- What this means for families trying to understand their risk
PCOS: A Polygenic Condition With Contributions From Both Parents
PCOS is now recognized as a polygenic condition, meaning many genes contribute to risk, and they can come from either parent. Twin studies show that up to 72% of the risk for developing PCOS is genetic, not exclusively maternal.
Genome-wide association studies have identified multiple gene regions tied to reproductive hormone signaling and metabolic traits, many of which can be inherited from fathers as well as mothers. These include genes involved in insulin signaling (INSR), gonadotropin activity (LHCGR, FSHR), and androgen pathways.
Paternal Health and PCOS Risk in Daughters
One of the most compelling pieces of evidence comes from a large population‑based study presented at the European Society of Human Reproduction and Embryology. Researchers found:
- Daughters had a higher risk of PCOS if their fathers had heart disease or stroke — double to triple the risk, depending on the condition.
- Diabetes in fathers was not a significant predictor.
This suggests the father’s cardiovascular and metabolic health may reflect underlying genetic risk factors that contribute to PCOS traits in daughters.
Why does this matter?
Cardiovascular risk traits — such as insulin resistance, dyslipidemia, and inflammatory signaling — share biological pathways with PCOS. If a father carries genetic variants predisposing him to these conditions, they may be passed to daughters, influencing ovarian function and hormone regulation.
Brothers of Women With PCOS May Show Related Metabolic Traits
PCOS is not only expressed in daughters. Research also shows that brothers of women with PCOS have a higher risk of insulin resistance or diabetes, suggesting that the genetic predisposition affects sons as well.
This finding reinforces the idea that:
- PCOS‑related genes are not sex‑limited.
- Fathers may carry the same variants but express them differently (as metabolic rather than reproductive traits).
- These shared variants can be passed to daughters, influencing their PCOS risk.
How Paternal Transmission May Work
1. Autosomal Gene Transmission
Because PCOS‑related genes are not located on sex chromosomes, they can be inherited equally from mother or father.
2. Cardiometabolic Trait Clustering
Fathers with:
- insulin resistance
- metabolic syndrome
- hypertension
- cardiovascular disease
may carry gene variants affecting insulin signaling, inflammation, or lipid pathways. These traits are closely intertwined with PCOS pathophysiology.
3. Epigenetic Effects
Paternal lifestyle, age, and metabolic health can influence sperm epigenetics — altering DNA methylation patterns that may affect daughters’ reproductive and metabolic health. Emerging epigenetic studies in PCOS suggest developmental programming plays a major role.
Does Having a Father With Health Problems Guarantee PCOS?
No — but it does increase risk.
PCOS heritability is estimated at up to 70%, yet known genetic variants explain only about 10% of cases directly. The remainder appears linked to:
- rare genetic variants
- epigenetic modifications
- developmental programming
- environmental exposures
Both maternal and paternal genetic contributions interact with these factors, shaping whether someone ultimately develops PCOS.
Clinical Implications: What Families Should Know
1. Family history should include both sides
When assessing PCOS risk, clinicians should ask about:
- father’s cardiovascular history
- father’s metabolic diseases (insulin resistance, diabetes, obesity)
- PCOS in female relatives on either side
2. Screening may need to start earlier
If a father has significant cardiometabolic disease, daughters may benefit from:
- earlier metabolic screening
- earlier evaluation for androgen excess
- preventative lifestyle guidance
3. Men should be aware of their own risks
Brothers and fathers of women with PCOS may have:
- higher cardiometabolic risk
- increased insulin resistance
- need for earlier screening and preventive counseling
Key Takeaways
- PCOS can be inherited from either parent — not just mothers.
- Fathers with heart disease or stroke double or triple their daughters’ PCOS risk.
- Brothers of women with PCOS show increased insulin resistance, supporting paternal genetic involvement.
- Up to 72% of PCOS risk is genetic, and many gene variants can be inherited through paternal lines.
- Epigenetic and developmental factors further shape how these risk genes are expressed.
