Defining the causes of sporadic Parkinson's disease in the global Parkinson's genetics program (GP2)

The Global Parkinson’s Genetics Program (GP2) will genotype over 150,000 participants from around the world, and integrate genetic and clinical data for use in large-scale analyses to dramatically expand our understanding of the genetic architecture of PD. This report details the workflow for cohort integration into the complex arm of GP2, and together with our outline of the monogenic hub in a companion paper, provides a generalizable blueprint for establishing large scale collaborative research consortia

Multi-ancestry genome-wide association meta-analysis of Parkinson?s disease

Although over 90 independent risk variants have been identified for Parkinson’s disease using genome-wide association studies, most studies have been performed in just one population at a time. Here we performed a large-scale multi-ancestry meta-analysis of Parkinson’s disease with 49,049 cases, 18,785 proxy cases and 2,458,063 controls including individuals of European, East Asian, Latin American and African ancestry. In a meta-analysis, we identified 78 independent genome-wide significant loci, including 12 potentially novel loci (MTF2, PIK3CA, ADD1, SYBU, IRS2, USP8, PIGL, FASN, MYLK2, USP25, EP300 and PPP6R2) and fine-mapped 6 putative causal variants at 6 known PD loci. By combining our results with publicly available eQTL data, we identified 25 putative risk genes in these novel loci whose expression is associated with PD risk. This work lays the groundwork for future efforts aimed at identifying PD loci in non-European populations

Different Nutrient Availabilities of Surface and Bottom Water under Nutrient-depleted Conditions during Bloom Formation of the Toxic Dinoflagellate Alexandrium tamarense in Osaka Bay, Japan

Alexandriium tamarense is a toxic dinoflagellate known to produce neurotoxins cause paralytic shellfish poisoning to human and marine animals. To understand the growth dynamics of A.tamarense, the seasonal changes in A,tamarense vegetative cells and environmental factors were evaluated using monthly field observations at two fixed stations in Osaka Bay, Japan, from January to May 2008. Additionally, a bioassay with axenic A.tamarense clonal cultures was performed to determine the growth potentials and growth-limiting nutrients of seawater samples collected during the field observations. The density of A.tamarense increased from February to April, and depletions of dissolved phosphate and silicate were observed in the surface layer during this period. The bioassay showed that phosphorous limitation occurred at the surface water of one station during March and April, while nitrogen limitation occurred in the bottom water. Moreover, at the other station, the growth potentials of the bottom water were higher than those of the surface water during February and April. Thus, the differences of nutrient availabilities between surface and bottom water during spring in Osaka Bay potentially allow A.tamarense to grow with nutrients uptake from bottom water by vertical migration

Distribution of Harmful Algal Growth-Limiting Bacteria on Artificially Introduced Ulva and Natural Macroalgal Beds

The intensity and frequency of harmful algal blooms (HABs) have increased, posing a threat to human seafood resources due to massive kills of cultured fish and toxin contamination of bivalves. In recent years, bacteria that inhibit the growth of HAB species were found to be densely populated on the biofilms of some macroalgal species, indicating the possible biological control of HABs by the artificial introduction of macroalgal beds. In this study, an artificially created Ulva pertusa bed using mobile floating cages and a natural macroalgal bed were studied to elucidate the distribution of algal growth-limiting bacteria (GLB). The density of GLB affecting fish-killing raphidophyteChattonella antiqua, and two harmful dinoflagellates, were detected between 10^6 and 10^7 CFU g^-1 wet weight on the biofilm of artificially introduced U. pertusa and 10 to 10^2 CFU mL^-1 from adjacent seawater; however, GLB found from natural macroalgal species targeted all tested HAB species (five species), ranging between 10^5 and 10^6 CFU g^-1 wet weight in density. These findings provide new ecological insights of GLB at macroalgal beds, and concurrently demonstrate the possible biological control of HABs by artificially introduced Ulva beds