PNPLA3 and Alzheimer disease: Total p-BCAAs concentration changed in the AD group comparing PNPLA3 CC and GG genotypes (CC: 612 ± 184 to 532 ± 149 μmol/g and GG: 587 ± 182 to 590 ± 130 μmol/g, p = 0.015 for time).