DNA consists of four chemical units, called nucleotide bases: adenine (A), thymine (T), guanine (G), and cytosine (C). These bases pair up with each other (A with T and C with G) to form units called ...

One goal of the project was to accurately sequence the 3 billion nucleotide base pairs in the human genome. A second goal was to map and identify all of the human genes present in the DNA sequence.

A single nucleotide polymorphism, or SNP, is a single base-pair difference in the DNA sequence of individual members of a species; not necessarily a pathological mutation, but commonly studied as ...