Data from: Genetic architecture and genomic patterns of gene flow between hybridizing species of Picea De La Torre, Amanda; Ingvarsson, Pär; Aitken, Sally N.
Hybrid zones provide an opportunity to study the effects of selection and gene flow in natural settings. We employed nuclear microsatellites (single sequence repeat (SSR)) and candidate gene single-nucleotide polymorphism markers (SNPs) to characterize the genetic architecture and patterns of interspecific gene flow in the Picea glauca × P. engelmannii hybrid zone across a broad latitudinal (40–60 degrees) and elevational (350–3500 m) range in western North America. Our results revealed a wide and complex hybrid zone with broad ancestry levels and low interspecific heterozygosity, shaped by asymmetric advanced-generation introgression, and low reproductive barriers between parental species. The clinal variation based on geographic variables, lack of concordance in clines among loci and the width of the hybrid zone points towards the maintenance of species integrity through environmental selection. Congruency between geographic and genomic clines suggests that loci with narrow clines are under strong selection, favoring either one parental species (directional selection) or their hybrids (overdominance) as a result of strong associations with climatic variables such as precipitation as snow and mean annual temperature. Cline movement due to past demographic events (evidenced by allelic richness and heterozygosity shifts from the average cline center) may explain the asymmetry in introgression and predominance of P. engelmannii found in this study. These results provide insights into the genetic architecture and fine-scale patterns of admixture, and identify loci that may be involved in reproductive barriers between the species.; Usage notes
DeLaTorre_Heredity_SSRdataText file showing genotypic data for 777 individuals from Picea glauca, Picea engelmannii and their hybrids, successfully amplified with ten SSR (microsatellite markers). First two columns indicate the population's and individual's IDs; columns 3 to 12, contain genotypic information (allele1/allele2). Missing values are represented by "NA".DeLaTorre_Heredity_SSR_TableS1Table S1 Characteristics of 10 nuclear microsatellites markers used in this study (adapted from Rungis et al., 2004). Microsatellite ID is used to identify individual loci in subsequent tables.
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