lethal mutation


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Related to lethal mutation: neutral mutation, Conditional lethal mutation

lethal mutation

[′lē·thəl myü′tā·shən]
(genetics)
References in periodicals archive ?
Selection is multiplicative across loci, so that a genotype with i heterozygous recessive lethal mutations has a relative fitness of [Mathematical Expression Omitted], where h is the dominance coefficient and the mean fitness in the population.
Identity disequilibrium, measured as the variance to mean ratio of number of recessive lethal mutations in adult plants, generally increases with increasing asexuality, both with respect to relative and absolute selfing rate [ILLUSTRATION FOR FIGURE 1C OMITTED].
All values reported for average number of lethals, inbreeding depression, and variance to mean ratio of recessive lethal mutations, are the values experienced during the sexual generation of the pseudoequilibrium cycles.
High inbreeding depression, selective interference among loci, and the threshold selfing rate for purging recessive lethal mutations.
Because populations of these species consist of several large clones, their genomic lethal mutation rates per sexual generation may be much higher.
We show that a large average number of recessive lethals (or lethal equivalents) per plant, maintained by a high genomic lethal mutation rate, interferes with the purging of lethals by self-fertilization.
As we shall see by comparison with the Kondrashov model, with genomic lethal mutation rates U [less than or equal to] 1, it gives a good indication of the mean number of nearly recessive lethals per plant even at intermediate selfing rates.
In designing such experiments, it is most straightforward to use microorganisms, given their short generation time and readily available conditional lethal mutations.
If lethal mutations are expressed earlier than less deleterious mutations, then the late expression of inbreeding depression in Mimulus suggests that mildly deleterious recessive mutations are the main cause of inbreeding depression in Mimulus.
Neutral mutations have no influence on the probability of extinction, whereas lethal mutations are eliminated in a single generation and have no cumulative effect.