SERPINA1 and relapsing-remitting multiple sclerosis: Of note, PI (EDSS/disease duration) was higher in the long AAT group (0.53±0.45 versus 0.31±0.27; p<0.01), according to the previous reported association between (AAT)n repeat polymorphism of CNR1 gene and disease progression in relapsing-remitting MS patients [36].