RPTN and Alzheimer disease: We have found that mRNA levels of FLG, FLG2, LOR, CRNN and SPRR3v1 were decreased (p ≤ 0.04), whereas mRNA levels of RPTN, HRNR and SPRR1Av1 were increased in lesional and nonlesional AD skin compared to the healthy control group (p ≤ 0.04).