Genetic Disease

Genetic Disease a genetic disease is a health condition caused by an abnormality in the genome. The genome is the total collection of genetic material which is organized inside the nucleus of a cell as microscopic assemblies known as chromosomes. The human genome consists of approximately 25,000 genes. A gene is a segment of DNA that influences a particular biological function and is passed down from parent to offspring. Genetic disease is caused by a change or mutation in single or multiple genes or a numerical or structural abnormality in the chromosome. The responsible mutation can occur in the embryonic stage (de novo mutation) or can be inherited from the parents. Genetic disorders passed from one or both parents to their offspring are inherited diseases.

In humans, there are 46 chromosomes. One pair member comes from the father, and the other comes from the mother. Out of these 23 pairs of chromosomes, 22 pairs are known as autosomes, and the last pair is called the sex chromosome. Each chromosome contains thousands of genes that perform a unique function. Sex chromosomes determine whether an organism is male or female. The autosomes are the same for males and females, but the combination of sex chromosomes is XY for males and XX for females. Genetic diseases are classified based on the type and location of the mutation, such as autosomal recessive, autosomal dominant, X-linked, Y-liked, and mitochondria-related.

Genetic diseases may also occur due to a numerical abnormality of the chromosomes, of which Down syndrome, Klinefelter, and Patau syndrome are notable. So far, more than 5,000 genetic diseases have been identified, and however, most of them are rare by themselves. [Sharif Akhteruzzaman]