TGFB1 and Alzheimer disease: Two studies demonstrated that the SNPs at codons + 10 (T/C) and + 25 (G/C), as well as the CC genotype of the TGF-β1 gene, which are associated with reduced TGF-β1 levels, have been linked to an increased conversion from MCI to AD [133, 134], whereas another research involving oldest-old individuals aged over 75 demonstrated that carriers of at least one minor T allele displayed a significant decline in cognitive and functional performance in the short-term, while those harboring the CC genotype of the TGF-β1 codon + 10 T > C polymorphism remained stable [135].