Recessive lethal

Definition

A recessive lethal gene is one that can cause death when present in two copies (homozygous), but has no lethal effect when only one copy is present (heterozygous). These genes often lead to the absence of individuals with certain genotypes from a population.

Related terms

Homozygous:

Having two identical alleles for a particular gene, which can result in displaying recessive traits or conditions if both alleles are recessive.

Heterozygous:

Having two different alleles for a particular gene, which can mask the expression of a recessive allele when paired with a dominant allele.

Genotype:

The genetic makeup of an organism in terms of its alleles, including those that may cause lethal effects when present in certain combinations