A point mutation is a type of mutation in DNA or RNA, the cell’s genetic material, in which one single nucleotide base is added, deleted or changed. DNA and RNA are made up of many nucleotides. There are five different molecules that can make up nitrogenous bases on nucleotides: cytosine, guanine, adenine, thymine (in DNA) and uracil (in RNA), abbreviated C, G, A, T, and U. The specific sequence of nucleotides encodes all the information for carrying out all cell processes. In general, a mutation is when a gene is altered through a change in DNA structure; this may refer even to entire sections of chromosomes. A point mutation is specifically when only one nucleotide base is changed in some way, although multiple point mutations can occur in one strand of DNA or RNA.