Except that she has the relevant expertise, and therefore this does not apply.

If we analyse it critically, there are six questions we can ask:

Expertise: How credible is the authority as a expert source?
Field: Is the authority an expert in a field relevant to the assertion?
Opinion: What does the authority assert that implies the assertion?
Trustworthiness: Is the expert personally reliable as a source?
Consistency: Is the assertion consistent with what other experts assert?
Backup evidence: Is the expert’s assertion based on evidence?

And on these regards we can say: she is credible, an expert in said field of genomics, and asserts that XX can be cis men too and vice versa; and she indeed is trustworthy, her assertions being consistent. Plenty of evidence to look it up.

I agree. Doctorate in Biology =/= Doctorate in Religion. She’s not right because she’s a doctor, she’s right because she’s right.