Project description:To identify novel mechanisms regulating allogeneic hematopoietic cell engraftment, we previously used a forward genetic approach and described identification, in mice, of the Bmgr5 bone marrow (BM) engraftment quantitative trait locus (QTL). This QTL confers dominant and large allele effects for engraftment susceptibility. It was localized to chromosome 16 by classical quantitative genetic techniques in a segregating backcross bred from susceptible BALB.K and resistant B10.BR mice. We now report verification of the Bmgr5 QTL using reciprocal chromosome 16 consomic strains. The BM engraftment phenotype in these consomic mice shows that Bmgr5 susceptibility alleles are not only sufficient but also indispensable for conferring permissiveness for allogeneic BM engraftment. Using panels of congenic mice, we resolved the Bmgr5 QTL into two separate subloci, termed Bmgr5a and Bmgr5b, each conferring permissiveness for the engraftment phenotype and both fine mapped to an interval amenable to positional cloning. Candidate Bmgr5 genes were then prioritized using whole exome DNA sequencing and microarray gene expression profiling. Further studies are needed to elucidate the genetic interaction between Bmgr5a and Bmgr5b and identify causative genes and underlying gene variants. This may lead to new approaches for overcoming the problem of graft rejection in clinical hematopoietic cell transplantation. B10.BALBChr16 and BALB.B10Chr16 consomic strain mice were constructed in our laboratory for validation of bone marrow engraftment and graft-vs-host diseaes QTLs. The parental strains for consomic line construction were B10.BR (B10.BR-H2k H2-T18a/SgSnJJrep) and BALB.K (C.C3-H2k/LilMcdJ). The JAX Mouse Diveristy 620K SNP Array was used to verify adequate removal of residual background heterozygosity. Liver DNA was delivered to JAX Mouse Diversity Genotyping Array Service (Jackson Laboratory) for the SNP Array genotyping.
Project description:To identify novel mechanisms regulating allogeneic hematopoietic cell engraftment, we previously used a forward genetic approach and described identification, in mice, of the Bmgr5 bone marrow (BM) engraftment quantitative trait locus (QTL). This QTL confers dominant and large allele effects for engraftment susceptibility. It was localized to chromosome 16 by classical quantitative genetic techniques in a segregating backcross bred from susceptible BALB.K and resistant B10.BR mice. We now report verification of the Bmgr5 QTL using reciprocal chromosome 16 consomic strains. The BM engraftment phenotype in these consomic mice shows that Bmgr5 susceptibility alleles are not only sufficient but also indispensable for conferring permissiveness for allogeneic BM engraftment. Using panels of congenic mice, we resolved the Bmgr5 QTL into two separate subloci, termed Bmgr5a and Bmgr5b, each conferring permissiveness for the engraftment phenotype and both fine mapped to an interval amenable to positional cloning. Candidate Bmgr5 genes were then prioritized using whole exome DNA sequencing and microarray gene expression profiling. Further studies are needed to elucidate the genetic interaction between Bmgr5a and Bmgr5b and identify causative genes and underlying gene variants. This may lead to new approaches for overcoming the problem of graft rejection in clinical hematopoietic cell transplantation.
Project description:Genome-wide SNP genotyping array can genotyped SNP highthroughly. It can be used in many aspects, such as phylogeny relationships, genome-wide association studies, copy number identification.
Project description:Comparison of Genotyping using pooled DNA samples (Allelotyping) and Individual Genotyping using the Affymetrix Genome-Wide Human SNP Array 6.0 In this study, data from 100 DNA samples individually genotyped with the Affymetrix Genome-Wide Human SNP Array 6.0 were used to estimate the error of the pooling approach by comparing the results with those obtained using the same array type but DNA pools each composed of 50 of the same samples. Newly developed and established methods for signal intensity correction were applied. Furthermore, the relative allele intensity signals (RAS) obtained by allelotyping were compared to the corresponding values derived from individual genotyping. Similarly, differences in RAS values between pools were determined and compared.
Project description:Using influenza A virus (IAV) infection in a mouse model of naturally selected genetic diversity, namely C57BL6/J (B6) mice carrying chromosomes (Chr) derived from the wild-derived and genetically divergent PWD/PhJ (PWD) mouse strain (B6.ChrPWD consomic mice), we examined the effects of genotype and sex on severity of IAV-induced disease To determine the role of genetic variation of host during IAV infection on gene expression, we performed RNAseq analysis on whole lung RNA isolated from two different mice.
Project description:CD23, the low affinity receptor for IgE, has been proposed to play a critical role in the regulation of IgE production, based on altered IgE levels in CD23-deficient mice and transgenic mouse models, as well as in mouse strains with mutations in the CD23 gene, e.g. 129 substrains. Here, we have investigated a mouse line termed LxT1 that expresses reduced CD23 surface levels on B cells, and its influence on IgE production. Extensive phenotypic analyses showed that CD23 surface expression was reduced in LxT1 compared to the control, without affecting B cell development in general. We linked the CD23low surface level in LxT1 mice to a recessive locus, a 129-derived region spanning 28Mb on chromosome 8, which includes the CD23 gene. Sequence analysis confirmed the five mutations within the CD23 coding region in LxT1 mice, the same as those present in NZB and 129 substrains. However, this CD23low phenotype was not observed in all 129 substrains despite carrying these same CD23 mutations in the coding region. Affymetrix Mouse Diversity Genotyping Array was performed according to the manufacturer's directions on DNA extracted from crossed mice samples. The array can interrogate more than 623,000SNPs, yielding an average SNP density of one marker per 4.3kb. Genetic linkage analysis was performed to exploit the co-segregation of chromosomal regions with the CD23 phenotype to identify the location of causative genes.