There is nothing in the books that I have read or online which suggest that Turkish Angora cats as a breed are hypoallergenic. However some individual cats might be.
The truth of the matter is that there are no cat breeds which are hypoallergenic. The only one that gets some sort of recognition as possibly being hypoallergenic is the Siberian Cat. But research does not support this anecdotal evidence.
Another cat breed which is said to be hypoallergenic is the Savannah. A first filial Savannah is in fact an Ashera GD which is one of the family of Allerca cats which are claimed to be hypoallergenic. This claim has been discredited, I believe. I believe that the company ceased doing business in 2015.
People, many people, are searching for a hypoallergenic cat because they love cats but are allergic to them to varying degrees. I believe that certain individual cats may be hypoallergenic. These individual cats may be part of a cat breed or they may be random bred cats. They are out there. Unneutered males are said to be more likely to cause an allergic reaction in people. I am not allergic to cats myself but one stray cat who I looked after made me itch so I was allergic to him. He was a male and he was unneutered.
I would proceed on the premise that it is not worth searching for a cat breed which is hypoallergenic. Some websites provide a list of hypoallergenic cat breeds but I’m afraid they are misleading you. If you’re desperate to look after a cat but are allergic to them, I would go to a cat shelter and sit with a cat for a while to see whether he or she induces an allergic reaction in yourself. If not then adopt the cat.