IL1A and Alzheimer disease: As for IL-1 family polymorphisms, lower serum BDNF was also associated with the presence of the T allele of IL-1α in AD (T carriers vs. CC homozygous, p = 0.040, Table 2), in particular in females, that showed the lowest BDNF levels (n = 26, 10.90 ± 2.84 pg/mL compared with both female controls (n = 14, 12.82 ± 1.91 pg/mL p = 0.009), males with AD (n = 15, 12.38 ± 1.86 pg/mL p = 0.046) (Figure 3), and female C/C homozygous with AD (n = 20, 12.74 ± 1.32 pg/mL p = 0.013).