Definition

Noun: A lethal gene is a gene whose presence or specific mutation results in the death of the organism carrying it. This fatal effect can occur at any stage of life, from embryonic development to adulthood.

Usage

The term is used in genetics and biology to describe a gene that, when expressed, is incompatible with life. It is a specific type of deleterious mutation. - It is typically discussed in the context of inheritance patterns, genetic disorders, and laboratory research. - The phrase is often used with verbs like carry, have, inherit, or express.

Examples

• The researchers identified a lethal gene that causes embryos to stop developing.
• If both parents carry the same lethal gene, there is a high probability their offspring will not survive.
• In fruit fly studies, certain lethal genes are used to understand essential developmental processes.

Advanced Usage

• Recessive Lethal Gene: A gene that only causes death when an individual has two copies (is homozygous) for the allele. Heterozygous carriers may be unaffected.
  • The mutation acts as a recessive lethal gene.
• Dominant Lethal Gene: A gene that causes death even when only one copy is present.
  • Huntington's disease is caused by a dominant lethal gene with late onset.

Variants and Related Words

• Lethal Allele: A more precise synonym often used interchangeably with "lethal gene," referring specifically to one of the variant forms of the gene.
• Conditional Lethal Gene: A gene that is lethal only under specific environmental conditions (e.g., a certain temperature).
• Sublethal Gene: A gene that severely impairs health or development but does not directly cause death.

Synonyms

• Lethal allele
• Lethal mutation
• Death gene (less common, more informal)

Related Phrases and Concepts

• Genetic Lethality: The phenomenon of death caused by genetic factors.
• Carrier of a lethal gene: An individual who possesses one copy of a recessive lethal gene but is phenotypically normal.
• Homozygous lethal: Describes the genotype (having two identical lethal alleles) that results in death.

Noun

1. any gene that has an effect that causes the death of the organism at any stage of life