A 1.5kb Psn promoter regulatory sequence (PEPC - Psn endogenous promoter cassette) drives expression of the longer isoform of Psn, mutated to carry an amino acid substitution that is equivalent to a E318G mutation in the orthologous human PSEN1 gene.
Based on statistical analysis of the age of onset and the severity of the phenotype, the following Psn alleles can be ranked in the following order, from strongest to weakest: PsnL166P.PEPC.L = PsnL173W.PEPC.L = PsnP436Q.PEPC.L = PsnV272A.PEPC.L = PsnL235P.PEPC.L > PsnM146L.PEPC.L = PsnM139V.PEPC.L = PsnH163R.PEPC.L = PsnE280A.PEPC.L = PsnA246E.PEPC.L = PsnG206A.PEPC.L > PsnA79V.PEPC.L = PsnF175S.PEPC.L = PsnE318G.PEPC.L.