THE PECULIAR RELATIONSHIP BETWEEN SICKLE CELL ANAEMIA AND MALARIA
A peculiar aspect about sickle cell anemia is that individuals who are carriers for the sickle cell gene are resistant to malaria, a life- threatening disease transmitted by the Anopheles mosquito.
A study conducted in the Gulbenkian Institute of Science in Oerias highlighted the mechanism behind this.
Mice were genetically modified to be carriers of the sickle cell allele. The researchers discovered that haem, a component of haemoglobin, was present in a free form in the blood of mice that carried the faulty haemoglobin gene. It was absent in normal mice. To test whether this resulted in the resistance, haem was introduced in the blood of normal mice. These mice did not develop malaria, hence confirming that the haem caused this resistance.
The free haem stimulates the production of an enzyme, oxygenase-1, that breaks it down. This enzyme releases small amounts of carbon monoxide, a toxic gas. To test whether this had a relation to malaria, the researchers introduced the malaria parasite into the systems of normal mice, and allowed them to inhale small quantities of CO. They did not develop the disease, hence proving that carbon monoxide impacted the onset of malaria in the mice.
There are many other factors which play a role in an individual being diagnosed with malaria, but this revelation could point to a potential cure to this fatal disease.