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Genetics and penis size

The role of genetics in determining penis size, including genetic factors and environmental influences.

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Jan 17, 2026
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Are there health or genetic factors associated with larger erect penis size?

Genetics are the single strongest predictor of penis size, but they interact with hormones, developmental health and environmental exposures so that “bigger” is rarely reducible to a single gene or si...

Jan 21, 2026

How do cultural and sampling differences affect reported average penis size across countries?

Reported cross‑national differences in average are shaped as much by who measures and how as by biology: large meta‑analyses find smaller, more uniform global averages than pop culture implies, but co...