Any gene that has an effect that causes the death of the organism at any stage of life.A genes whose effect on the phenotype is profoundly negative, and causes the organism to exhibit many disadvantageous characteristics, which can eventually lead to death.lethal gene
a gene that produces a genotype that leads to death of the organism before reproduction is possible or that precludes reproduction; for a recessive gene the homozygous or hemizygous state is lethal.
Dictionary > Lethal Gene
