E1b1a haplogroup and Sickle Cell disease

Some time back we had talked about how Gene Therapy, which is essentially a way of throwing out defective genes from one’s body and replacing them with normal ones, was instrumental in curing Sickle Cell Anemia.

Sickle Cell Anemia is basically a disorder wherein the blood cell which should essentially be round like Oreos morph into a Sickle like a Jellybean gone rogue. This leads to the morphed sickle cells to lock into each other and block the flow of blood, causing excruciating pain.

One of the most peculiar traits of the Sickle cell anemia was the people who suffer from it. As it turns out the biggest victims of Sickle cell disease are Africans or those having African origins. According to WHO in certain areas of Africa as many as 10-40% of the people display traits of the disease.

So why are people from Africa so prone to this disease? The most acceptable answer to this question is that the genetic variant called HbS which causes Sickle Cell disease is actually a boon against another deadly disease in Africa: Malaria.

As the Malaria parasite enters the human’s bloodstream it starts destroying the normal blood cells which carry oxygen around the body. As it turns out there are two ways by which the Sickle cell aids in the fight against Malaria. One, as the body sends the sickle blood cells to the spleen for elimination, the Malaria parasite which has also infected the sickle cell gets eliminated and two the sickle cell leaks the nutrients like potassium which are present in it. These nutrients are what feeds the parasite and it dies shortly due to hunger.

This is a perfect example of the human body creating a much bigger problem in order to get rid of a relatively smaller one(malaria).

This Sickle Cell disease is really not a race thing and the regions which have a higher prevalence of Malaria also have a higher prevalence of the Sickle cell disease.

But that’s not the end of the story, as a matter of fact, the reason we wrote this article was we found something really interesting. First let us look at the image below:

Notice something similar? Well as it turns out, the continental distribution of the Sickle cell disease is almost similar to the distribution of the E1b1a Haplogroup. So was the Sickle cell disease influenced not just by the prevalence of malaria but also by the E1b1a Haplogroup?

So where is the E1b1a haplogroup prevalent?

As the figure showed, mainly Western, Central, Southern Africa is home to the E1b1a haplogroup and going by the Sickle Cell stats, in a study conducted it was found that 4% of the cases originated in America, 16% in Asia and a whopping 80% mainly originated in these prevalent regions of E1b1a.

To further drill home the point, let’s seek refuge in history. Egyptian pharos who are most famous for providing loads of documentary content to Discovery and National Geographic are also a key character in this story.

King Tutankhamen the kid who became a Pharoh around 1341 BC had died untimely at the age of 19. Apart from the usual bout of “he was murdered” conspiracy theories, malaria was largely held as his cause of death. But recent discoveries have suggested that Sickle cell disease was the real reason. Plus Egyptian mummies as early as 3200 BC have found to have suffered from Sickle cell disease.

This piece of information is key because Pharos like Ramesses III are known to have also possessed the haplogroup E1b1a which makes it likely that the whole royal lineage had this haplogroup. Now Sickle cell first arrived in Egypt at about 10,000 years which had led to the speculation that the flow of Sickle Cell was predominately influenced by the flow of the E1b1a haplogroup which originated around 25,000 – 30,000 BC at the horn of Africa. The disease though was only ‘’aided’’ in its spread by the selective pressure of malaria.

So let’s have a go at it again. It is believed that those regions having a tendency of a malaria outbreak are home to the sickle cell disease. But the image we put out showed a similarity between the distribution of the Sickle cell gene and the E1b1a haplogroup. Also, the prevalence of both these traits in the Egyptian royalty means that the Sickle Cell spread right around the time the E1b1a haplogroup was spreading. Hence maybe both weren’t mutually exclusive but were actually correlated?

So does the E1b1a haplogroup somehow aid the morphing of blood cells in the form of a sickle? Some evidence does point in that direction but for a concrete theory, we might just have to wait for some time…

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Categories: E, Other

Tags: E1b1a, Genetic Disorders, Malaria

Race and Intelligence Genetic History of Africa