The analysis of AD risk related to the status of PRNP codon 129 (Table 3) indicated a non-significant association trend for the M129 allele (OR = 1.23, p = 0.057), as well as for the M129M (OR = 1.47) and M129V (OR = 1.16) genotypes compared to homozygous V129V for the whole AD population. Here, PRNP is linked to Alzheimer disease.