Monogenic Disorders:
Monogenic disorders happen when there’s a mutation (change) in a single gene, causing it to become defective.
Around 4000 such disorders are known.
These disorders happen when abnormal genes either produce too little or no product, leading to health problems.
Some disorders may even cause death at a young age.
Examples include Hutchinson’s disease, Tay-Sachs disease, galactosemia, phenylketonuria, sickle-cell anemia, cystic fibrosis, albinism, hemophilia, and night blindness.
1. Albinism:
Albinism is a genetic disorder.
Normally, our skin, hair, and eyes get their colour from a pigment called melanin.
In albinism, the body cannot produce melanin, causing pale skin, white hair, and pinkish eyes.
2. Sickle-Cell Anemia:
Small changes in the structure of proteins or DNA can cause diseases.
In sickle-cell anemia, the normal hemoglobin (the part of blood that carries oxygen) has an important change: glutamic acid (a part of the hemoglobin) is replaced by valine.
This causes red blood cells, which are normally round, to become sickle-shaped.
These sickle-shaped cells do not carry oxygen well, leading to various problems like blocking blood vessels and damaging organs.
Sickle-cell anemia is inherited, meaning it’s passed down from parents to children.
If both parents have the disease or carry the gene for it, their child may have sickle-cell anemia.
There are two types of people affected by sickle-cell anemia:
Carriers (AS) – They carry the gene but may not show symptoms.
Sufferers (SS) – They have the disease and show symptoms.
Symptoms of Sickle-Cell Anemia:
Swollen hands and feet
Joint pain
Body aches
Frequent colds and coughs
Low-grade fever
Feeling very tired
Pale skin
Low hemoglobin levels