Example of Mendelian Disorder

Some of the most common mendelian disorders are as follows:

Hemophilia

It is a genetic disease, which prevents blood from clotting normally, even slight accidents can result in significant bleeding. Hemophilia is an autosomal recessive condition in which the body is unable to manufacture the clotting proteins.

Color blindness

A recessive sex-linked condition known as color blindness occurs when the eye cannot tell the difference between red and green. The gene for normal vision is dominant. X-chromosomes carry the normal gene and its recessive allele.

Sickle-cell anemia

It is an autosomal genetic condition that affects the hemoglobin molecules, the protein that carries oxygen in red blood cells. Red blood cells with sickle shapes are formed when mutant hemoglobin molecules bind to one another and form stiff, rod-like formations. These cells are rigid and have an uneven shape, which makes them difficult to pass through the smallest blood channels. In certain veins, RBCs frequently build up and form clots.

Phenylketonuria

Phenylketonuria (PKU) is an inherited recessive disorder during which the levels of an amino acid called phenylalanine are increased in the blood. This means that both alleles of the gene in each cell have mutations. Both the parents of an individual with this autosomal recessive condition carry one copy of the mutated gene each, but they act as carriers of the disease.

Cystic fibrosis

It is a genetic recessive disorder in which the lungs and the digestive system get blocked with abnormally thick and sticky mucus. Cystic fibrosis is caused by a single recessive gene that regulates the enzyme responsible for producing the glycoprotein. Both copies of the gene in each cell have mutations because this disorder is inherited in an autosomal recessive way.

Tay-Sachs disease

The brain deteriorates as a result of the genetic, Tay-Sachs illness. The Tay-Sachs allele encodes a defective version of the hexosaminidase A enzyme, which causes the disease. Gangliosides, a group of lipids found in the lysosomes of brain cells, are broken down by this enzyme. As a result, gangliosides accumulate in the lysosomes, which then expand and finally burst, releasing oxidative enzymes that cause cell death. This condition has no known treatment. Moreover, this illness has an autosomal recessive inheritance pattern.

Mendelian disorders are a form of genetic disorder that is caused by the inheritance of single or multiple mutant genes from one or both parents. The function of the mutant gene determines how severe a Mendelian disorder is. The condition is typically severe if the gene controls a crucial function. Mendelian diseases include, for instance, Tay-Sachs disease, sickle cell anemia, and cystic fibrosis. These illnesses can be fatal and range in severity from mild to severe.