In order to find some initial sources, I simply googled ‘The Causes of Transsexualism’, ‘Gender Identity’, ‘Transsexualism’ etc. and filtered for relevant material.
One source that I think will be useful is the NHS website: http://www.nhs.uk/Conditions/Gender-dysphoria/Pages/Causes.aspx
Additionally, I have found some online articles that may provide a starting point for some of the theories I could discuss:
- Conway L. (2001-2) How Frequently Does Transsexualism Occur? http://ai.eecs.umich.edu/people/conway/TS/TSprevalence.html
- Transas City. Una (2013). The Transgender Brain | Transas City. Available at: http://transascity.org/the-transgender-brain/.
- Ekins R. King D. (2001) Transgendering, migrating and love of oneself as a woman. International Journal of Transgenderism. 5(3) https://www.atria.nl/ezines/web/IJT/97-03/numbers/symposion/ijtvo05no03_01.htm
From my google search, I found the wikipedia entry: https://en.wikipedia.org/wiki/Causes_of_transsexuality
This suggested some potential theories I may want to look at such as Blanchards Theory of Autogynephelia which is discussed in the third bulletpoint link above. I also read briefly about a case called The John/Joan study which I would like to read more about.
My initial source, however, will be ‘The Transsexual Scientist’ by Dana Bevan which offers information about the causes of Transsexualism from a scientific and personal point of view. I discovered this source by similiar search methods mentioned above, on amazon books.