Single-gene and chromosome disorders

 Sexual living organisms have two types of cells: somatic and genetic. Somatic mutation happens with body cells while gametic mutation happens with sex cells and can be pass on to the next generation such as how HIVs are passed on genetically. Mistake from the replication of DNA or the chromosomes can cause mutation and variation in the body. There are two majors way that causes mutation: chemical or radiation and evolving over time to the environment according to Darwin's laws on natural selection.

Chances of DNA failing to replicate the exact  duplicate is really low, however once it has been synthesize wrongly, it could affect the entire individual and lead to mutation or changes in the individual. The modification in autosomes may lead to diseases such as Down syndrome, Edward’s syndrome or fatau's syndrome where there is one extra chromosome (3 chromosomes instead of 2 chromosomes). Since the gene is coded inside the DNA, the disease can be pass on to the next generation as well. In addition, if an individual is missing an autosome, they will result in being handicapped where they might be missing an arm or they might have a volvuli heart disease.

This article on chromosome disorders interested me because I personally know many individual with down syndromes. I think it is pretty amazing how small structure units such as chromosomes have the ability to control and impact the entire living organism.