NCI Dictionary of Genetics Terms
Welcome to the NCI Dictionary of Genetics Terms, which contains technical definitions for more than 150 terms related to genetics. These definitions were developed by the PDQ® Cancer Genetics Editorial Board to support the evidence-based, peer-reviewed PDQ cancer genetics information summaries.
- heterozygous genotype
- listen (HEH-teh-roh-ZY-gus JEE-noh-tipe)
Occurs when the two alleles at a particular gene locus are different. A heterozygous genotype may include one normal allele and one mutation, or two different mutations. The latter is called a compound heterozygote.