Just for context, the first half dozen expeditions into pre-revolutionary war Michigan resulted in a high death rate from malaria.
A one-time gene mutation in a West African human millennia ago gave them immunity to malaria and doomed some of their descendants to sickle cell anaemia, according to new research.
Today, about 300,000 children are born with sickle cell anaemia every year, with that number expected to rise to 400,000 in the next 30 years. The majority of these cases occur in Nigeria, the Democratic Republic of Congo, and India, and many of these babies are likely to die from the disease in which their red blood cells break apart, leaving their bodies starved of oxygen. It is caused by two copies of a gene mutation in their DNA. One copy is harmless; two copies can be deadly. Millions of people worldwide, frequently those with African heritage, are carriers of this mutant gene, but there are large gaps in our knowledge of the disease and its characteristic mutations.
Sickle cell anaemia contributes the equivalent of 5% of deaths of under-five-year-old children on the African continent, according to the W.H.O, more than 9% of such deaths in west Africa, and up to 16% of under-five deaths in individual west African countries.
The new research, published in scientific journal Cell, has found that this disease began with a single ancestor who developed the mutation to fend of malaria.