A1 types, release neurotoxins that lead to cell death and development of neurodegenerative diseases, while A2 type, support neuronal survival and tissue repair through expression and releasing various trophic factors such as transforming growth factor‐β (TGF‐β) which plays a neuroprotective role and participates in synaptogenesis.52, 53. This evidence concerns the gene TGFB1 and neurodegenerative disease.