How common is the sickle cell trait?
In Jamaica about 10% of the population have the sickle cell trait but in other islands the frequency varies from 7% in Barbados to as high as 13-14% in Dominica and St. Lucia. This compares to 8% in the Afro-American population, and frequencies of 20-30% in the populations of West Africa and of some populations in Saudi Arabia, India, Greece and Italy.
