At that time homosexual acts were illegal and as a punishment Turing was given the choice of prison or experimental hormone treatment.
He took the latter and received injections of the female hormone oestrogen, which led him to develop breasts.
He was also barred from working for the government due to a fear at the time that homosexuals could be communist spies.
Two years later Turing was found dead after apparantly biting into a posioned apple. He was 42 years old.