The threads are composed of paired strands of nucleotides or base pairs. There are 3.2 billion base pairs in the human genome and 80,000 to 100,000 genes. In most cases such DNA changes either have no effect or cause harm. Occasionally, however, a mutation can improve an organism's chance of surviving and passing the beneficial change on to its descendants. A large complex molecule made up of one or more chains of amino acids.
Proteins perform a wide variety of activities in the cell.
Sometimes confused with DNA, RNA is a group of nucleic acids that along with DNA comprises the genetic material of the cell. Genetic information is stored by DNA in the nucleus of cells, and RNA carries that information to other parts of the cell where it is converted into protein. The process of identifying the order in which chains of repeating units of base pairs appear in DNA and identifying the order of amino acids in proteins. Researchers label copies of a DNA sequence with fluorescent markers, then run them through a sequencing machine. In proteins, amino acids are removed one at a time from the end of a protein and identified with an automated system.