Deleterious mutations and the evolution of sexual reproduction

  title={Deleterious mutations and the evolution of sexual reproduction},
  author={Alexey S. Kondrashov},
The origin and maintenance of sexual reproduction continues to be an important problem in evolutionary biology. If the deleterious mutation rate per genome per generation is greater than 1, then the greater efficiency of selection against these mutations in sexual populations may be responsible for the evolution of sex and related phenomena. In modern human populations detrimental mutations with small individual effects are probably accumulating faster than they are being eliminated by… 

Recessive mutations and the maintenance of sex in structured populations.

It is shown that low levels of population structure or inbreeding can greatly enhance the importance of recessive deleterious mutations in the context of sexual vs. asexual populations.


The results suggest that the two processes operating simultaneously may select for sex independent of the exact shape of the function that maps mutation number onto host fitness.

Evolutionary traction: the cost of adaptation and the evolution of sex

It is shown that without recombination, rare advantageous mutations can result in increased accumulation of deleterious mutations (‘evolutionary traction’), which explains the long‐term advantage of sex under a wide parameter range.

The evolution of sex and recombination.

Mutation load depending on variance in reproductive success and mating system.

To keep a balance between retaining genetic variability and minimizing the increase of the mutation load, equalization of reproductive success of a set of individuals rather than of every individual might be more advantageous.

Origins of eukaryotic sexual reproduction.

Using the perspectives of molecular genetics and cell biology, documented and hypothetical scenarios for the instantiation and evolution of meiosis, fertilization, sex determination, uniparental inheritance of organelle genomes, and speciation are considered.

Evolutionary biology: Sex and synergism

Testing principles that provide the central debating point at a meeting that dealt with the evolution and maintenance of sex found that testing these principles is by no means easy.



Environmental change, mutational load and the advantage of sexual reproduction

It is shown that the re-establishment of equilibrium following environmental change is generally faster in sexual populations, and that the mutational load experienced by the sexual population can be significantly less during this period than that experienced by an asexual one.

The consequences of mutation in multi-clonal asexual species

The consequences of favourable and deleterious mutations in an asexual population with two alleles A and a are considered and sex prevents clonal loss and permits the existence of intense variation.

Mutational load and the advantage of sex

The mutational load for dominant deleterious mutations is 2u in sexual populations, but this reduces to between 2u and u when the selective disadvantage of the heterozygote is less than about 0·03, and the situation is different in the case of asexual population.

Evolution of sex in RNA viruses.

  • L. Chao
  • Biology
    Journal of theoretical biology
  • 1988

Deleterious mutations as an evolutionary factor. 1. The advantage of recombination.

A population with u deleterious mutations per genome per generation is considered in which only those individuals that carry less than a critical number of k mutations are viable and selection at a locus that determines recombination frequency of the whole genome is considered.

Accumulation of mutations in sexual and asexual populations.

It is shown that the rates of accumulation of both beneficial and harmful mutations with weak selection depend on the within-population variance of the number of mutant genes per genome, which is largest in a selfing population and smallest in an asexual population.

Biased conversion as the primary function of recombination.

It is shown that a conversion process directed against the most common type of genetic damage can substantially reduce the mutational load, even if the Conversion force is weak and if the conversion process occasionally creates new mutations.

Genetic Loads and the Cost of Natural Selection

In his early papers on natural selection, Haldane was concerned with both the dynamics and the statics of evolution, and emphasized that, although evolution depends on changes of gene frequency, nevertheless at any one time the population is in approximate equilibrium for most factors.

The evolution of meiosis and sexual reproduction

A conclusion is that the authors have been misled by treating meiosis and genetic recombination as more or less synonomous and it is pointed out that recombination could give the most immediate advantage early in the origin of life, particularly with a hypercycle model.