Question

What are the 3 types of genetic disorders?

Answer 1

Genetic disorders:

Genetic disorders are those diseases which are not happening due to environmental changes but they happen due to the change in the genetic sequence of the individual.

The types of genetic disorders are as follows:

• Complex disorders (mutation in two or more genes)

1. In these disorders the genetic variation occurs in two or more than 2 genes.

• For example rheumatoid arthritis, multiple sclerosis, scleroderma, and SLE.

1. In SLE the genes involved are HLA-DR1, HLA-DR3 etc.
2. Single gene disorders
3. These disorders occur due to defect in a single gene.
4. For example in sickle cell anaemia, Duchenne muscular dystrophy, cystic fibrosis, and haemochromatosis.
5. In sickle cell anaemia on chromosome 11 a single base pair is replaced due to which betaglobin protein is replaced by Valine resulting in this deformity.

• Chromosomal abnormalities

1. Chromosomal abnormalities occur due to defect in the entire chromosome.
2. For example down syndrome, Turner syndrome, and Klinefelter syndrome.
3. Down syndrome occurs due to trisomy of 21st chromosome.