- The physical site or location of a specific gene on a chromosome
Definition from: GeneReviews
from the University of Washington and the National Center for Biotechnology Information
- A locus is the specific physical location of a gene or other DNA sequence on a chromosome, like a genetic street address. The plural of locus is "loci".
Definition from: Talking Glossary of Genetic Terms from the National Human Genome Research Institute
See also Understanding Medical Terminology.