Unexpected meeting of two separate lines of research resulted in the discovery of oncogenes. Oncogenes are deoxyribonucleic acid (DNA) sequences coding for polypeptide gene products which cause, or contribute to, neoplastic growth of cells. Oncogenes remain almost unchanged through evolution: oncogenes and their gene products of avian, murine, feline, simian and human species show close homolog...

Carcinogenesis is a multi-step process which result in uncontrolled cell growth. Mutations in DNA that lead to cancer disrupt these orderly processes by disrupting the programming regulating the processes.. This results in uncontrolled cell division leading to carcinogenesis. Oncogenes are genes whose protein products stimulate or enhance the division and viability of cells. Oncogenes arise by ...

Retroviruses code for oncogenes which cause tumors in animals. The viral oncogenes have evolved from normal cellular proto-oncogenes, to which they are closely related. The viral and cellular oncogenes differ in point mutations and size, the viral genes often being truncated and, in some cases, fused to unrelated cellular genes. These differences may be responsible for the transforming function...