For a quantitative trait under stabilizing selection, the effect of epistasis on its genetic architecture and on the changes of genetic variance caused by bottlenecking were investigated using theory and simulation. Assuming empirical estimates of the rate and effects of mutations and the intensity of selection, we assessed the impact of two-locus epistasis (synergistic/antagonistic) among linked or unlinked loci on the distribution of effects and frequencies of segregating loci in populations at the mutation-selection-drift balance. Strong pervasive epistasis did not modify substantially the genetic properties of the trait and, therefore, the most likely explanation for the low amount of variation usually accounted by the loci detected in genome-wide association analyses is that many causal loci will pass undetected. We investigated the impact of epistasis on the changes in genetic variance components when large populations were subjected to successive bottlenecks of different sizes, considering the action of genetic drift, operating singly (D), or jointly with mutation (MD) and selection (MSD). An initial increase of the different components of the genetic variance, as well as a dramatic acceleration of the between-line divergence, were always associated with synergistic epistasis but were strongly constrained by selection.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/evo.12413 | DOI Listing |
Discov Oncol
January 2025
Department of Clinical Laboratory, Affiliated Hospital of Guangdong Medical University, No. 57 South Renmin Avenue, Xiashan District, Zhanjiang, 524001, People's Republic of China.
Objective: Circulating protein level ratios (CPLRs) may play a crucial role in tumor progression and drug resistance by mediating interactions within the tumor microenvironment. This study aims to investigate the causal associations between CPLRs and papillary thyroid cancer (PTC), focusing on their potential implications in drug resistance mechanisms.
Methods: Genetic data for 2821 CPLRs were obtained from the GWAS and FinnGen databases.
Am J Med Genet B Neuropsychiatr Genet
January 2025
Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
BackgroundInsomnia is a common neurological disorder that exhibits connections with the gut microbiota; however, the exact causal relationship remains unclear. MethodsWe conducted a Mendelian randomization (MR) study to systematically evaluate the causal effects of genus-level gut microbiota on insomnia risk in individuals of European ancestry. Summary-level datasets on gut microbiota were sourced from the genome-wide association study (GWAS) of MiBioGen, while datasets on insomnia were obtained from the GWAS of Neale Lab and FinnGen.
View Article and Find Full Text PDFJ Cosmet Dermatol
January 2025
Department of Neonatology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China.
Background: The skin microbiota, a complex community of microorganisms residing on the skin, plays a crucial role in maintaining skin health and overall homeostasis. Recent research has suggested that alterations in the composition and function of the skin microbiota may influence the aging process. However, the causal relationships between specific skin microbiota and biological aging remain unclear.
View Article and Find Full Text PDFAm J Bot
January 2025
Department of Ecology, Evolution and Behavior, University of Minnesota Twin Cities, St Paul, 55108, MN, USA.
Premise: Prairies are among the most threatened biomes due to changing patterns of climate and land use, yet information on genetic variation in key species that would inform conservation is often limited. We assessed evidence for the geographic scale of population-level variation in growth of two species of prairie clover and of their symbiotic associations with nitrogen-fixing bacteria.
Methods: Seed representing two species, Dalea candida and D.
Hereditas
January 2025
The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, No. 182 Chunhui Road, Longmatan District, Luzhou, Sichuan, 646000, China.
Background: Alzheimer's disease (AD) is a prevalent neurodegenerative disorder, with antibody-mediated immune responses to infectious diseases agents potentially playing a decisive role in its pathophysiological process. However, the causal relationship between antibodies and AD remains unclear.
Methods: A two-sample Mendelian randomization (MR) analysis was conducted to investigate the causal link between antibody-mediated immune responses to infectious diseases agents and the risk of AD.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!