One in 25 Caucasians is a carrier for the defective CFTR gene,making it the most common genetic disease in this population.Why would the frequency of defects in CFTR be so common in this population,given the relationship between cholera and CFTR is similar in humans?

Question

Quizplus · Accepted Answer

Studies have shown that individuals who carry one copy of the defective CFTR gene (heterozygotes) may have increased resistance to cholera compared to those with no defective copies (wild-type homozygotes). This is because the CFTR protein regulates chloride and bicarbonate ion transport in the gastrointestinal tract, and cholera toxin activates this pathway. Heterozygotes may have a mild increase in chloride and bicarbonate secretion, which can help flush out the cholera bacteria. This could explain why the defective CFTR gene is relatively common in Caucasian populations, which have historically been exposed to cholera.

One in 25 Caucasians Is a Carrier for the Defective