{"title":"存在表观相互作用时的误差阈值","authors":"David A. Herrera-Martí","doi":"arxiv-2409.11944","DOIUrl":null,"url":null,"abstract":"Models for viral populations with high replication error rates (such as RNA\nviruses) rely on the quasi-species concept, in which mutational pressure beyond\nthe so-called ``Error Threshold\" leads to a loss of essential genetic\ninformation and population collapse, an effect known as the ``Error\nCatastrophe\". We explain how crossing this threshold, as a result of increasing\nmutation rates, can be understood as a second order phase transition, even in\nthe presence of lethal mutations. In particular, we show that, in fitness\nlandscapes with a single peak, this collapse is equivalent to a\nferro-paramagnetic transition, where the back-mutation rate plays the role of\nthe external magnetic field. We then generalise this framework to rugged\nfitness landscapes, like the ones that arise from epistatic interactions, and\nprovide numerical evidence that there is a transition from a high average\nfitness regime to a low average fitness one, similarly to single-peaked\nlandscapes. The onset of the transition is heralded by a sudden change in the\nsusceptibility to changes in the mutation rate. We use insight from Replica\nSymmetry Breaking mechanisms in spin glasses, in particular by considering that\nthe fluctuations of the genotype similarity distribution are an order\nparameter.","PeriodicalId":501040,"journal":{"name":"arXiv - PHYS - Biological Physics","volume":"2 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Error Thresholds in Presence of Epistatic Interactions\",\"authors\":\"David A. Herrera-Martí\",\"doi\":\"arxiv-2409.11944\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Models for viral populations with high replication error rates (such as RNA\\nviruses) rely on the quasi-species concept, in which mutational pressure beyond\\nthe so-called ``Error Threshold\\\" leads to a loss of essential genetic\\ninformation and population collapse, an effect known as the ``Error\\nCatastrophe\\\". We explain how crossing this threshold, as a result of increasing\\nmutation rates, can be understood as a second order phase transition, even in\\nthe presence of lethal mutations. In particular, we show that, in fitness\\nlandscapes with a single peak, this collapse is equivalent to a\\nferro-paramagnetic transition, where the back-mutation rate plays the role of\\nthe external magnetic field. We then generalise this framework to rugged\\nfitness landscapes, like the ones that arise from epistatic interactions, and\\nprovide numerical evidence that there is a transition from a high average\\nfitness regime to a low average fitness one, similarly to single-peaked\\nlandscapes. The onset of the transition is heralded by a sudden change in the\\nsusceptibility to changes in the mutation rate. We use insight from Replica\\nSymmetry Breaking mechanisms in spin glasses, in particular by considering that\\nthe fluctuations of the genotype similarity distribution are an order\\nparameter.\",\"PeriodicalId\":501040,\"journal\":{\"name\":\"arXiv - PHYS - Biological Physics\",\"volume\":\"2 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-09-18\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - PHYS - Biological Physics\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2409.11944\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - PHYS - Biological Physics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2409.11944","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Error Thresholds in Presence of Epistatic Interactions
Models for viral populations with high replication error rates (such as RNA
viruses) rely on the quasi-species concept, in which mutational pressure beyond
the so-called ``Error Threshold" leads to a loss of essential genetic
information and population collapse, an effect known as the ``Error
Catastrophe". We explain how crossing this threshold, as a result of increasing
mutation rates, can be understood as a second order phase transition, even in
the presence of lethal mutations. In particular, we show that, in fitness
landscapes with a single peak, this collapse is equivalent to a
ferro-paramagnetic transition, where the back-mutation rate plays the role of
the external magnetic field. We then generalise this framework to rugged
fitness landscapes, like the ones that arise from epistatic interactions, and
provide numerical evidence that there is a transition from a high average
fitness regime to a low average fitness one, similarly to single-peaked
landscapes. The onset of the transition is heralded by a sudden change in the
susceptibility to changes in the mutation rate. We use insight from Replica
Symmetry Breaking mechanisms in spin glasses, in particular by considering that
the fluctuations of the genotype similarity distribution are an order
parameter.