Context

• World Sickle Cell Day is observed on June 19.

What is sickle cell anaemia?

• It is an inherited genetic disease. Haemoglobin which is tasked with carrying oxygen to all parts of the body has four protein subunits — two alpha and two beta. In some people, mutations in the gene that creates the beta subunits impact the shape of the blood cell and distort it to look like a sickle, similar to the letter C. 
• A round red blood cell can move easily through blood vessels because of its shape but sickle red blood cells end up slowing and even blocking the blood flow. Moreover, sickle cells die early, resulting in a shortage of red blood cells that deprive the body of oxygen. 
• These obstructions and shortages may cause chronic anaemia, pain, fatigue, acute chest syndrome, stroke, and a host of other serious health complications. 
• India is the second-worst affected country in terms of predicted births with SCA — i.e. chances of being born with the condition.

Prevalence

• The disease burden from Sickle Cell anaemia in India is prevalent in tribal populations. Tribes like Pawara, Bhil, Madia, Gond and Pardhan from Maharashtra have a very high prevalence. 
• Sickle cell anaemia is most prevalent in the central India belt covering states like Gujarat, Maharashtra, Chhattisgarh, Orissa and parts of Bengal. There are pockets in the south, Tamil Nadu, Kerala and parts of Telangana.

Why is Sickle Cell anaemia under-diagnosed? 

• There is a lack of screening awareness and inadequate screening centres/facilities in tribal and rural areas. Also, failure to access primary healthcare is a concern. 

Treatment

• Sickle cell anaemia is a genetic disorder, making complete “elimination” a challenge that requires a major scientific breakthrough. 
• The only cure comes in the form of gene therapy and stem cell transplants — both costly and still in developmental stages. 
• In gene therapy, the DNA inside the haemoglobin gene is edited to stop the disease while in stem cell transplants, the bone marrow affected by sickle cell anaemia is replaced with healthy bone marrow from a donor. Both interventions are currently being tested in clinical trials globally. 
• Blood transfusion, wherein red blood cells are removed from donated blood and given to a patient, is also a trusted treatment in the absence of permanent cures. But challenges include a scarcity of donors, fears around safe supply of blood, risk of infection etc.

https://pib.gov.in/PressReleasePage.aspx?PRID=1933456