Genes are the basic unit that indicates the function of the human body. In humans, a cell nucleus contains 23 pairs of chromosomes, each pair is inherited from mother and the other pair from father. There are hundreds to thousands of genes in one chromosome. Each human cell has around 23,000 genes. Genes are made up of DNA that contain the basic physical and functional unit of heredity. In humans, more than 99.9% of our DNA sequence is identical. The remaining small differences between us contribute to the unique physical and chemical features called genetic variation. This genetic variation determines our difference in appearances, personalities, genetic traits as well as disease susceptibility and individual’s drug response.
Genetics is the studies of a single gene’s structure, function, and variation, transmission, and expression of genes. Genomics is genetics on a larger scale. Genomics study the complete set of DNA in order to gain insight on the structure and functioning of the genetic material. Genetic screening identifies hereditary conditions on at-risk individual that may cause neuro degeneration or response to drugs. The screening process is safe and non-invasive.