[SamReidHughes]

Twin studies are mostly used to show that traits are heritable at an individual level.

Edit: It strikes me that the strawman argument you've constructed is a perfect example of left-wing science denial. The endemic use of the technique in fields like psychology, criminology, biology, is something you prefer to ignore.

[astrange]

"Heritable" doesn't mean "genetic" or "inherent to a person".

[inter_netuser]

does "genetic" mean "inherent to the person"?

[astrange]

I wouldn't agree with that either, but most people would, so might as well stick it in there.

Let's say it's part of the causal chain, but also your cells don't even have the same genome, it mutates over time, women integrate cells from their children, so it gets messy.

[ABeeSea]

Can you link to a specific study that you claim is left wing science denial?