Haemoglobinopathies can be the worst inherited diseases sometimes. Sickle cell disease is also one of the haemoglobinopathies caused due to point mutation. According to WHO, around 30000 babies are born with such disorders annually. However, around 5% of the world’s population are healthy carriers of sickle cell anaemia.
What is sickle cell disease?
In this disease, there is a defect in the hemoglobin chain synthesis. HB is a protein that gives a red color to human blood. The proteins are composed of chains of subunits called amino acids. In this disease, the amino acid synthesis is disturbed. Therefore, the non-polar amino acid called valine replaces the acidic glutamic acid at position 6. This results in a defect in HB chain synthesis.
Valine is non-polar, so it condenses to form long strands. These strands are fibres that make the cell appear sickle-shaped. This is a primary protein structure defect. The normal life span of human erythrocytes is 120 days. However, the sickle cells die within 10-20 days of birth. This is a huge gap and shows adverse effects on the human body. This also promotes marrow hyperplasia.
Normal erythrocytes are biconcave discs, whereas affected cells are sickle shaped. The sickle cells promote clumping in the blood. This results in scarce distribution of oxygen to the organs. However, the change in shape also affects the transport of oxygen in the body.
Diagnosis
Haemoglobin electrophoresis technique is used to detect Sickle cell disease. It is a common practice that uses electrical measures to diagnose. The HBS migrates to the electrodes at a very slow speed. However, HBA (normal haemoglobin) migrates faster. This is because of the reduction in the acidity of the chain.
An interesting fact:
Patients with sickle cell anaemia would never suffer from malaria. This is because the plasmodium parasite needs to complete its lifecycle in the human erythrocytes (life span: 120 days). When the lifespan is greatly reduced they can’t complete their lifecycle in the meantime. Hence, they die along with RBCs.
Symptoms of Sickle-cell Anemia
Infants usually don’t show symptoms until they are 5-6 years old. In severe cases, anaemia leads to chronic, acute pain syndromes and other pathological infections. However, the symptoms include:
- Swelling of feet and hands
- Delayed Puberty
- The patient suffers vision problems
- Spleen damage
- Jaundice
- Yellow skin tone
This disease is very painful. On this World Sickle Cell Day let’s pledge that we will always encourage the suffering ones. Government must assure proper treatments to every patient, and adequate facilities must be available for every person.
Read about the reduction of grey matter of human brain due to covid19 here.
