Furthermore, in order to calculate the proportion of the PSA glycoforms in which GalNAc is present in the B fractions from aggressive PCa blood serum samples, PCa1, PCa5 and PCa6 were further digested with ABS and ABS + BTG (BTG releases β1-3,4 galactose) (Fig. 5). The gene discussed is KLK3; the disease is posterior cortical atrophy.