Project description:Gene expression in the islets of diseased NOD mice compared to congenic healthy NOD.B10 mice at various ages, during the progression of NOD disease.
Project description:To characterize the genetic basis of hybrid male sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL). Many trans eQTL cluster into eleven ‘hotspots,’ seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL - but not cis eQTL - were substantially lower when mapping was restricted to a ‘fertile’ subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility.
Project description:We collected whole genome testis expression data from hybrid zone mice. We integrated GWAS mapping of testis expression traits and low testis weight to gain insight into the genetic basis of hybrid male sterility.
Project description:This experiment is one of a series of experiments on interspecific recombinant congenic strain (IRCS) mice that aimed to identify novel genes involved in male or female hyporfertility by comparing characteristics of the sperm, number of offspring, quality of implantation etc. in C57B6/J and IRCS mice. <br>The goal of this experiment was to understand the basis of female hypofertility/embryonic resorption in a mouse model of congenic strains. The IRCS strain used in this experiment is the 66H Ch13 mouse. This strain was derived by introgression of a ~6 Mb fragment of mus spretus origin inside the genome of Mus musculus (C57B6/J) (L'hôte et al, Bioessays, 2010. PMID:20091755 ) Previous ultrasonographic analysis of this line revealed an increased rate of embryonic resorption compared to the C57B6/J parent (Laissue et al, Int. J . Dev. Biol, 2009 PMID: 19488966 ). <br>In this experiment we measured gene expression in the tissues that are relevant for implantation and early development, i.e. the uterus and the placenta, in C57B6/J and 66H Chr13 mice at 12 days post-coïtus with C57B6/J males. Pools of RNA from four mice per sample were obtained and analysed using a Nimblegen mouse expression array.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:We collected whole genome testis expression data from hybrid zone mice. We integrated GWAS mapping of testis expression traits and low testis weight to gain insight into the genetic basis of hybrid male sterility. Gene expression was measured in whole testis from males aged 62-86 days. Samples include 190 first generation lab-bred male offspring of wild-caught mice from the Mus musculus musculus - M. m. domesticus hybrid zone.
