Molecular drive is an evolutionary process, like natural selection and driftปกติ, that changes the genetic composition of a population, through the generations. It is distinct from natural selection and neutral drift in that it emerges from the activities of a number of ubiquitous mechanisms of DNA turnover (MOT), such as gene conversion, unequal crossing over, slippage, transposition, retrotransposition and so on.
So, how does it work?
Consider a single mutation arising at a single location, on a single chromosome, in a single individual. The theories of natural selection and neutral drift assume that this mutation cannot increase in frequency in a population under its own steam because the chromosome on which it resides obeys Mendel's rules of inheritance, which in turn depend on the random assortment of chromosomes at meiosis. By contrast, all MOT are essentially non-mendelian, in that the initial mutant sequence can increase or decrease in copy number within the lifetime of an individual. Take, for example, gene conversion, whereby one allelic version of a gene is converted to the sequence of another version on the homologous chromosome, such that Aabecomes AA or aa.
Molecular drive is an evolutionary process, like natural selection and driftปกติ, that changes the genetic composition of a population, through the generations. It is distinct from natural selection and neutral drift in that it emerges from the activities of a number of ubiquitous mechanisms of DNA turnover (MOT), such as gene conversion, unequal crossing over, slippage, transposition, retrotransposition and so on.
So, how does it work?
Consider a single mutation arising at a single location, on a single chromosome, in a single individual. The theories of natural selection and neutral drift assume that this mutation cannot increase in frequency in a population under its own steam because the chromosome on which it resides obeys Mendel's rules of inheritance, which in turn depend on the random assortment of chromosomes at meiosis. By contrast, all MOT are essentially non-mendelian, in that the initial mutant sequence can increase or decrease in copy number within the lifetime of an individual. Take, for example, gene conversion, whereby one allelic version of a gene is converted to the sequence of another version on the homologous chromosome, such that Aabecomes AA or aa.
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