I wish I could find it for you. You might try googling something like "brain research and genetics" or something similar. I googled it and got links to a lot of scholarly papers.
This topic is fascinating! I have read several stories about twins, and once about triplets, who were adopted by different families at birth. The triplets all went through a period of being very troublesome in their teens at the same time. One set of twins used the same obscure brand of toothpaste, and both had married a woman named Debbie, divorced, and then both married a woman named Linda!
Good luck with your search. Let me know what you learn.