I'm quoting an article here and it varies by race. "The prevalence is between 3 and 7 per 100,000 in populations of western European descent. HD appears less common in Japan, China, Finland, and African blacks. The frequency of HD in Japan has been estimated at between 0.1 and 0.38 per 100,000. The prevalence of HD exceeds 15 per 100,000 in some populations that are mostly of western European origin ." Cristy told me that 30,000 people are affected in the US with 150,000 estimated at risk.
Hope this helps,
Steve
