For the white population, the prevalence ratio
of multiple sclerosis per 100,000 population was 44.9
in the first region and 44.4
in the second. The prevalence of multiple sclerosis in Gypsies was found to be 19.1/100,000 in the first region and 18.4 in the second. It is concluded that multiple sclerosis is less common in Gypsies than in whites living in the same areas."
It appears that a combination of genetics and environment might be a factor ...