Day 12: Favism

Today we talked about Favism and how it is a specific genetic mutation.

Favism is a modern medical disease. It was first noticed after the Korean war when soldiers were taking a drug called primaquine to not risk catching malaria and this caused them to die suddenly. This is because some of the soldiers had Favism which is a deficiency mutation on the X chromosome. This is more common in men because they only have one X chromosome unlike women who have two X chromosomes so it is less likely to affect them. The deficiency mutation is when the cells lack an important enzyme called G6PD which acts like a "bouncer" for all the free radicals that seek red blood cells and attack them. If you don't have enough G6PD then free radicals can attack your blood cells and make them burst. Eating fava beans releases  free radicals in the form of covicine and vicine  that attack the cells that don't have enough G6PD and the person can die. G6PD deficiency occurs a lot in the places were fava beans are part of the staple diet which is where they are grown in the Mediterranean area. Malaria parasites do not like G6PD deficient cells so they won't attack them. So it is favored to eat fava beans for anti-malaria protection. That is why the malaria medicine also has a lot of free radicals.

Other Plants like fava beans release chemicals sometimes that serves as a defense. For example in the cassava plant if you eat it raw you will die from the cyanide produced in the skin. It produces cyanide to be protected from being predated upon a lot. Cassava will also produce a lot of cyanide in drought because it wants to survive till the next rain. In chili peppers their defense is the spicy capascin that discourages animals to eat it. The animals can't handle the taste so they won't eat the chili peppers. The peppers don't want to be eaten by the mammals because their stomach is a bad condition for their seeds to survive and get excreted and "planted" in another area. Birds on the other hand don't taste this capascin so they are "allowed" to eat the chili so they can carry their seeds in their weak digestive system.