Regions of lower crossing over harbor more rare variants in African populations of Drosophila melanogaster.
نویسندگان
چکیده
A correlation between diversity levels and rates of recombination is predicted both by models of positive selection, such as hitchhiking associated with the rapid fixation of advantageous mutations, and by models of purifying selection against strongly deleterious mutations (commonly referred to as "background selection"). With parameter values appropriate for Drosophila populations, only the first class of models predicts a marked skew in the frequency spectrum of linked neutral variants, relative to a neutral model. Here, we consider 29 loci scattered throughout the Drosophila melanogaster genome. We show that, in African populations, a summary of the frequency spectrum of polymorphic mutations is positively correlated with the meiotic rate of crossing over. This pattern is demonstrated to be unlikely under a model of background selection. Models of weakly deleterious selection are not expected to produce both the observed correlation and the extent to which nucleotide diversity is reduced in regions of low (but nonzero) recombination. Thus, of existing models, hitchhiking due to the recurrent fixation of advantageous variants is the most plausible explanation for the data.
منابع مشابه
Linkage disequilibrium patterns across a recombination gradient in African Drosophila melanogaster.
Previous multilocus surveys of nucleotide polymorphism have documented a genome-wide excess of intralocus linkage disequilibrium (LD) in Drosophila melanogaster and D. simulans relative to expectations based on estimated mutation and recombination rates and observed levels of diversity. These studies examined patterns of variation from predominantly non-African populations that are thought to h...
متن کاملDNA sequence polymorphism and divergence at the erect wing and suppressor of sable loci of Drosophila melanogaster and D. simulans.
Several evolutionary models of linked selection (e.g., genetic hitchhiking, background selection, and random environment) predict a reduction in polymorphism relative to divergence in genomic regions where the rate of crossing over per physical distance is restricted. We tested this prediction near the telomere of the Drosophila melanogaster and D. simulans X chromosome at two loci, erect wing ...
متن کاملEvolution at the tip and base of the X chromosome in an African population of Drosophila melanogaster.
Hitchhiking effects of advantageous mutations have been invoked to explain reduced polymorphism in regions of low crossing-over in Drosophila. Besides reducing DNA heterozygosity, hitchhiking effects should produce strong linkage disequilibrium and a frequency spectrum skewed toward an excess of rare polymorphisms (compared to the neutral expectation). We measured DNA polymorphism in a Zimbabwe...
متن کاملToxicological Evaluation of a New Lepidopteran Insecticide, Flubendiamide, in Non-Target Drosophila melanogaster Meigen (Diptera: Drosophilidae)
Background: Flubendiamide, comparatively a new pesticide designed to eradicate lepidopteran insect pests is known to have low risk to birds, mammals, fish, algae, honey bees, non-target arthropods, earthworms, soil macro- and micro-organisms, non-target plants as well as sewage treatment organisms; however, the risk assessment for aquatic invertebrates from metabolite could not be finalized wit...
متن کاملContrasting patterns of X-linked and autosomal nucleotide variation in Drosophila melanogaster and Drosophila simulans.
Surveys of molecular variation in Drosophila melanogaster and Drosophila simulans have suggested that diversity outside of Africa is a subset of that within Africa. It has been argued that reduced levels of diversity in non-African populations reflect a population bottleneck, adaptation to temperate climates, or both. Here, I summarize the available single-nucleotide polymorphism data for both ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Genetics
دوره 158 2 شماره
صفحات -
تاریخ انتشار 2001