Question

Are gender distinctions consistent across cultures?

Answer 1

Yes.

Explanation:

You have a couple of very broad definitions (distinction and culture) and one very specific biological fact (sex/gender). Given the factual minority occurrence of even psychological definitions of other than two genders, the distinctions across cultures are negligible.

Attempts to distinguish between sex and gender are primarily semantic, as one is an apparent and obvious fact and the other is a psychologically self-defined lifestyle option. Acceptance of "alternative gender" orientations in different cultures do vary, but those differences are consistent, which is different than saying that they are the same. That is, the relative acceptance of "gender" outside of the binary sexual attributes is consistent across culture types defined by religious beliefs, community size and external contacts.

See also:
http://www.med.monash.edu.au/gendermed/sexandgender.html