Prevalence
ΔF508 is present in approximately one in 30 Caucasians. Scientists have estimated that the mutation occurred over 52,000 years ago in Northern Europe. One theory as to why the otherwise detrimental mutation has evolved is that it exerts a positive effect by reducing water-loss during cholera, a common cause of death in Europe when the mutation first appeared. Another theory posits that CF carriers (heterozygotes for ΔF508) are more resistant to Typhoid fever since CFTR has been shown to act as a receptor for Salmonella typhi bacteria into epithelial cells.
Read more about this topic: Delta F508
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