Who is At Risk?

HSAN IV is actually an extremely rare disease where the occurrence of it is very low. However, the prevalence of the disease is still unknown (National Organization for Rare Disorders, 2014). HSAN IV affects male and female equally and a lot of cases have been reported in Japan especially, more than any other countries. The frequency of this disease is higher in the Japanese and Israeli-Bedouin populations due to founder effect (National Organization for Rare Disorders, 2014). Founder effect occurs when a small isolated population (the founders) expands over several generations, resulting to a high prevalence of a particular genetic trait within the population. Thus, it reduces the genetic diversity within the population (Matute, 2013). Onset of the disorder is at birth (National Organization for Rare Disorders, 2014).

References:

Matute, D. R. (2013). The role of founder effects on the evolution of reproductive isolation. Journal of Evolutionary Biology, 26(11), 2299-2311.