What are DNA and Genes?
All genetic tests involve the assessment of DNA (deoxyribonucleic acid), which contains the code used in the growth and function of all living organisms. The main function of DNA is the storage of information; the instructions contained within DNA are used to construct other components of cells, which are the fundamental working units of every living organism. The sections of DNA that carry this ‘genetic’ information are called genes. Within cells, DNA is organized into structures called chromosomes. Humans have a total of 46 chromosomes, matched in two pairs of 23 chromosomes each. The set of chromosomes in a cell make up its genome, and the complete set of this information in an organism is called its genotype. Chromosomes are comprised of physically separate molecules of DNA that range in length from about 50 million to 250 million base pairs of cross-linked, repeating units called nucleotides. Genes are located at specific positions on particular chromosomes that represent the fund
