B19 wrote:
It is now thought by geneticists that DNA mutations can occur to the foetus after conception and before birth. This is now thought to explain why identical twins can be significantly different - and re autism, why one identical twin can be on the spectrum and the other not. The old assumption that both are subject to exactly the same conditions is a developing area of inquiry, and it is a very interesting one.
In my only family there is evidence of AS for five generations, the two before mine and the two after mine, and in the fifth generation (my grandchildren) there are one set of fraternal male twins. Both are AS though they manifest it in different ways. One is quite extroverted, very gifted in maths, science and athletic ability, and highly competitive and independent; the other is introverted with average scholastic ability, profoundly interested in the natural world, a gentle soul who does his best in everything and needs a lot of emotional support and reassurance. (Their parents are my NT daughter and my AS son-in-law), but as genes are inherited as well from grandparents, and of the 4 grandparents, 2 of us ,( the paternal grandfather and myself, the maternal grandmother) are on the spectrum, so I would say that in our family AS arises from genetics rather than any mutation after conception.
However given the explosion of new genetic knowledge in the past 15 years, I would think that the next ten years will see some extraordinary progress in building on the work to date in this field.
The mutation after conception theory is more compelling in the case of those families in whom no-one has AS and then it suddenly appears in one child. I look forward to more knowledge developing in this body of research.
^^ identical twin differences explained well here by B19. Absolutely fascinating reading about your family B19. How do you feel diagnosis and support has changed over the generations?
This is fascinating. I wonder WHAT might cause the DNA to mutate?