A gene is a segment of DNA that carries the information needed by the cell to construct a protein. Which protein that is, when it is made, and how damage to it can give rise to genetic disease all depend on the gene's sequence. In other words, they depend on how the building blocks of DNA, the nucleotides A, C, G, and T (adenine, cytosine, guanine, and thymine) are ordered along the DNA strand. For example, part of a gene may contain the base sequence TGGCAC, while part of another gene may contain the base sequence TCACGG. Knowing a gene's base sequence can lead to isolation of its protein product, show how individuals are related, or point the way to a cure for those people carrying it in its damaged form.

Overview

In 1977 two methods for sequencing DNA were introduced. One method, referred to as Maxam-Gilbert...