The genotype analysis of the B*27:05 carriers, 73 pEBNA3A responders and 29 non-responders, pointed out that the AS protective variants, especially those of ERAP1, were more frequent in the cohort of pEBNA3A non-responders (both AS patients and HD), although a significant difference was found only for the rs30187 polymorphism (Table 1). Here, ERAP1 is linked to Huntington disease.