Sensitive Detection of Chromosomal Segments of Distinct Ancestry in Admixed Populations

Identifying the ancestry of chromosomal segments of distinct ancestry has a wide range of applications from disease mapping to learning about history. Most methods require the use of unlinked markers; but, using all markers from genome-wide scanning arrays, it should in principle be possible to infer the ancestry of even very small segments with exquisite accuracy. We describe a method, HAPMIX, which employs an explicit population genetic model to perform such local ancestry inference based on fine-scale variation data. We show that HAPMIX outperforms other methods, and we explore its utility for inferring ancestry, learning about ancestral populations, and inferring dates of admixture. We validate the method empirically by applying it to populations that have experienced recent and ancient admixture: 935 African Americans from the United States and 29 Mozabites from North Africa. HAPMIX will be of particular utility for mapping disease genes in recently admixed populations, as its accurate estimates of local ancestry permit admixture and case-control association signals to be combined, enabling more powerful tests of association than with either signal alone.     

Group 1 metabotropic glutamate receptors 1 and 5 form a protein complex in mouse hippocampus and cortex

The group 1 metabotropic glutamate receptors 1 and 5 (mGluR1/5) have been implicated in mechanisms of synaptic plasticity and may serve as potential therapeutic targets in autism spectrum disorders. The interactome of group 1 mGluRs has remained largely unresolved. Using a knockout‐controlled interaction proteomics strategy we examined the mGluR5 protein complex in two brain regions, hippocampus and cortex, and identified mGluR1 as its major interactor in addition to the well described Homer proteins. We confirmed the presence of mGluR1/5 complex by (i) reverse immunoprecipitation using an mGluR1 antibody to pulldown mGluR5 from hippocampal tissue, (ii) coexpression in HEK293 cells followed by coimmunoprecipitation to reveal the direct interaction of mGluR1 and 5, and (iii) superresolution microscopy imaging of hippocampal primary neurons to show colocalization of the mGluR1/5 in the synapse.     

Role of functional polymorphism of matrix metalloproteinase-2 (-1306 C/T and -168 G/T) and MMP-9 (-1562 C/T) promoter in oral submucous fibrosis and head and neck squamous cell carcinoma in an Indian population

The aim of this study was to explore the association of MMP-2 (-1306 C/T and -168 G/T) and MMP-9 (-1562 C/T) promoter polymorphisms in oral submucous fibrosis (OSMF) and head and neck squamous cell carcinoma (HNSCC) cases. These SNP were genotyped by PCR-RFLP. Total of 1260 individuals were recruited, of which 412 OSMF, 422 HNSCC and 426 were controls. In HNSCC, MMP-2 (-1306 C/T) and MMP-9 (-1562C/T) polymorphism, T allele showed strong association (p < 0.00 and p < 0.01) as compared to healthy control respectively, but not in case of OSMF and showed significant association with increasing progression of clinico-pathological grading. We concluded that SNPs in the MMP-2 and -9 promoter region may be associated with susceptibility to HNSCC not in OSMF.     

Characterization of polymorphic microsatellite markers and genetic diversity in wild bronze featherback, Notopterus notopterus (Pallas, 1769)

Six polymorphic microsatellite DNA loci were identified in the primitive fish, bronze featherback, Notopterus notopterus for the first time and demonstrated significant population genetic structure. Out of the six primers, one primer (NN90) was specific to N. notopterus (microsatellite sequence within the RAG1 gene) and five primers were product of successful cross-species amplification. Sixty-four primers available from 3 fish species of order Osteoglossiformes and families Notopteridae and Osteoglossidae were tested to amplify homologous microsatellite loci in N. notopterus. Fifteen primer pairs exhibited successful cross-priming PCR product. However, polymorphism was detected only at five loci. To assess the significance of these six loci (including NN90) in population genetic study, 215 samples of N. notopterus from five rivers, viz Satluj, Gomti, Yamuna, Brahmaputra and Mahanadi were analyzed. The five sample sets displayed different diversity levels and observed heterozygosity ranged from 0.6036 to 0.7373. Significant genotype heterogeneity (P < 0.0001) and high F_ST (0.2205) over all loci indicated that the samples are not drawn from the same genepool. The identified microsatellite loci are promising for use in fine-scale population structure analysis of N. notopterus.     

Comparative transcriptome mining for terpenoid biosynthetic pathway genes in wild and cultivated species of Plantago

Protoplasma - Plantagos are important economical and medicinal plants that possess several bioactive secondary metabolites, such as phenolics, iridoids, triterpenes, and alkaloids. Triterpenoids...