Not sure if this has been posted previously, but 'POST' a parliamentary newsletter/info thingy are doing a briefing on gender dysphoria and are looking for expertise to inform it. I have come across POST briefings in my own line of work (that is how I happened on this one) and I think they can be quite useful and well informed.
They do ask for your 'credentials' before requesting evidence, but I know there are some people on MN who have relevant professional experience, so thought I'd flag it up.
https://post.parliament.uk/approved-work-determinants-of-distress-associated-with-gender-identity/
FYI, here is how they describe what they do: "POST is a bicameral body that bridges research and policy. One of our key activities is writing short, impartial, and accessible evidence syntheses. These briefings, commonly known as POSTnotes, tackle a range of topics in science, technology and the social sciences. POSTnotes are designed for Members of Parliament. But they are also used by many other stakeholders, such as government, the media and the third sector. To make sure they are comprehensive and balanced, we need insights from the expert community. This includes experts from academia, industry, government, the third sector and beyond. Could that be you?"