 Absence of Pin1 activity in humans has also been implicated in the folding and processing of the amyloid precursor protein, whose degradation product is the cytotoxic peptide amyloid beta implicated in Alzheimer's disease.In addition to Pin1, higher eukaryotes contain one more parvulin gene, whose core sequence is highly conserved in all multi-cellular organisms examined so far, but absent from yeast.In humans the locus of this parvulin resides on chromosome Xq13 and is encoding two protein species, Par14 and Par17.