Standard Article

Genes: Definition and Structure

  1. Millard Susman

Published Online: 3 MAY 2005

DOI: 10.1038/npg.els.0003852



How to Cite

Susman, M. 2005. Genes: Definition and Structure. eLS. .

Author Information

  1. University of Wisconsin, Madison, Wisconsin, USA

Publication History

  1. Published Online: 3 MAY 2005

This is not the most recent version of the article. View current version (15 JUL 2014)


The word ‘gene’ has two meanings: (1) the determinant of an observable trait or characteristic of an organism, or (2) the DNA sequence that determines the chemical structure of a specific polypeptide molecule or RNA molecule. Since the observable characteristics of organisms include the chemical structures of their constituent molecules, these two definitions merge at the molecular level.


  • gene;
  • cistron;
  • genetic code;
  • gene expression;
  • gene regulation