Novel genetic loci associated with hippocampal volume

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness

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Not AvailableAiming at verifying the effect of host on the development, the biology of Rhyzopertha Dominica (Fab.) was studied on paddy variety, Sumati, Maize Hybrid DHM-111 and sorghum variety M 35-1 during 2009-10 in the Department of Entomology, College of Agriculture, Rajendranagar, Hyderabad. The biological parameters assessed were egg duration, egg hatching percentage, total larval and pupal period, total development period, fecundity, male and female longevity, sex ratio, pre-oviposition, oviposition and post oviposition period. When R. Dominica was reared on paddy, maize and sorghum the egg period was lowest in paddy variety sumati (6.57) and highest in maize hybrid DHM 111 (7.72). The egg hatching percentage is lowest in Maize Hybrid, DHM-111 (68.48±3.95) and highest in case of sorghum var. M 35-1 (73.65±5.12). The total larval and pupal period shortest in sorghum var. M 35-1 (35.35±1.95) and highest in Maize Hybrid, DHM-111 (43.85±1.45). The shortest total developmental period of 42.17±2.13 and 41.63±2.17 were recorded in male and female of R. Dominica in sorghum var. M 35-1 and the longest developmental period of 51.57±1.28 and 50.77±1.14 were recoreded in males and females of R. Dominica in case of Maize Hybrid, DHM-111. In all the three hosts it was found that the longevity of female was longer than male. The shortest pre-oviposition, oviposition and post oviposition periods of 4.03±0.67, 31.33±2.41, 6.13±0.73 days were recorded in Maize Hybrid DHM- 111 respectively. The results obtained shows that among the three host grains used for the study, Maize hybrid was found to be the least preferred host, followed by paddy variety, Sumati and sorghum variety, M 35-1.Not Availabl

Temperature and pH define the realised niche space of arbuscular mycorrhizal fungi

The arbuscular mycorrhizal (AM) fungi are a globally distributed group of soil organisms that play critical roles in ecosystem function. However, the ecological niches of individual AM fungal taxa are poorly understood. We collected > 300 soil samples from natural ecosystems worldwide and modelled the realised niches of AM fungal virtual taxa (VT; approximately species‐level phylogroups). We found that environmental and spatial variables jointly explained VT distribution worldwide, with temperature and pH being the most important abiotic drivers, and spatial effects generally occurring at local to regional scales. While dispersal limitation could explain some variation in VT distribution, VT relative abundance was almost exclusively driven by environmental variables. Several environmental and spatial effects on VT distribution and relative abundance were correlated with phylogeny, indicating that closely related VT exhibit similar niche optima and widths. Major clades within the Glomeraceae exhibited distinct niche optima, Acaulosporaceae generally had niche optima in low pH and low temperature conditions, and Gigasporaceae generally had niche optima in high precipitation conditions. Identification of the realised niche space occupied by individual and phylogenetic groups of soil microbial taxa provides a basis for building detailed hypotheses about how soil communities respond to gradients and manipulation in ecosystems worldwide

Novel genetic loci associated with hippocampal volume

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness