有害な突然変異の間の干渉は,有限な集団における性別と再結合を好む
Peter D Keightley1, Sarah P Otto
1Institute of Evolutionary Biology, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK. keightley.nature2006@spambob.net
Nature
|September 8, 2006
まとめ
進化にとって極めて重要な性や再結合は,背景選択によって説明される. このプロセスは遺伝的多様性を高め,適応を向上させ,有害な突然変異を排除します,特に大きな集団では.
科学分野:
- 進化生物学の進化生物学について
- 人口遺伝学 人口遺伝学
背景:
- セックスと再結合は,広範な進化的現象である.
- その適応的優位性を説明することは,進化生物学における長年の課題である.
- 以前の理論は,適応的置換とミュラーのラチェットに焦点を当てており,変異率と集団の大きさに基づいた制限がありました.
研究 の 目的:
- 性および再結合の進化を推進する背景選択の役割を調査する.
- 再結合がストキャスティック・アドバンテージをもたらすメカニズムを解明する.
- 性繁殖の普及について,堅実な説明を提供すること.
主な方法:
- 性別と再結合の頻度に影響を与えるトレーキング変異性アレル.
- 背景選択が遺伝的多様性や適応に与える影響を分析する.
- Hill-Robertson効果を有限な集団で調査する.
主要な成果:
- 背景選択は,性別と再結合にストキャスティック上の優位性を与え,集団の大きさとともに増加します.
- 低再結合レベルは,ヒル・ロバートソン効果による効果的な集団サイズと遺伝的多様性を減少させます.
- セックスと再結合は,隠された遺伝的多様性を明らかにし,適応を向上させ,有害な変異を浄化する.
結論:
- 背景選択は,再結合の進化上の利点について広く適用可能な説明を提供します.
- このメカニズムは頑丈で,有害なアレル間のエピスタティック相互作用から大きく独立しています.
- この発見は,高額なセックスと人口における再結合の広がりを説明するものである.
関連する概念動画
Mismatch Repair
Overview
Mutation, Gene Flow, and Genetic Drift
In a population that is not at Hardy-Weinberg equilibrium, the frequency of alleles changes over time. Therefore, any deviations from the five conditions of Hardy-Weinberg equilibrium can alter the genetic variation of a given population. Conditions that change the genetic variability of a population include mutations, natural selection, non-random mating, gene flow, and genetic drift (small population size).Mechanisms of Genetic VariationThe original sources of genetic variation are mutations,...
Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
Mismatch Repair
Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
Crossing Over
Crossing over is the exchange of genetic information between homologous chromosomes during prophase I of meiosis I. Genetic recombination gives rise to allelic diversity in the newly formed daughter cells. In humans, crossing over produces genetically distinct haploid egg and sperm cells that undergo fertilization to produce unique offspring. Before cell division starts, the germ cell’s chromosome(s) undergo duplication in the S phase of the cell cycle. As the cells enter prophase I, duplicated...


