Multi-ancestry genome-wide association study of 21,000 cases and 95,000 controls identifies new risk loci for atopic dermatitis

Genetic association studies have identified 21 loci associated with atopic dermatitis risk predominantly in populations of European ancestry. To identify further susceptibility loci for this common, complex skin disease, we performed a meta-analysis of >15 million genetic variants in 21,399 cases and 95,464 controls from populations of European, African, Japanese and Latino ancestry, followed by replication in 32,059 cases and 228,628 controls from 18 studies. We identified ten new risk loci, bringing the total number of known atopic dermatitis risk loci to 31 (with new secondary signals at four of these loci). Notably, the new loci include candidate genes with roles in the regulation of innate host defenses and T cell function, underscoring the important contribution of (auto)immune mechanisms to atopic dermatitis pathogenesis

Spatio-temporal variability of copepod abundance along the 20 °S monitoring transect in the Northern Benguela upwelling system from 2005 to 2011.

Long-term data sets are essential to understand climate-induced variability in marine ecosystems. This study provides the first comprehensive analysis of longer-term temporal and spatial variations in zooplankton abundance and copepod community structure in the northern Benguela upwelling system from 2005 to 2011. Samples were collected from the upper 200 m along a transect at 20 °S perpendicular to the coast of Namibia to 70 nm offshore. Based on seasonal and interannual trends in surface temperature and salinity, three distinct time periods were discernible with stronger upwelling in spring and extensive warm-water intrusions in late summer, thus, high temperature amplitudes, in the years 2005/06 and 2010/11, and less intensive upwelling followed by weaker warm-water intrusions from 2008/09 to 2009/10. Zooplankton abundance reflected these changes with higher numbers in 2005/06 and 2010/11. In contrast, zooplankton density was lower in 2008/09 and 2009/10, when temperature gradients from spring to late summer were less pronounced. Spatially, copepod abundance tended to be highest between 30 and 60 nautical miles off the coast, coinciding with the shelf break and continental slope. The dominant larger calanoid copepods were Calanoides carinatus, Metridia lucens and Nannocalanus minor. On all three scales studied, i.e. spatially from the coast to offshore waters as well as temporally, both seasonally and interannually, maximum zooplankton abundance was not coupled to the coldest temperature regime, and hence strongest upwelling intensity. Pronounced temperature amplitudes, and therefore strong gradients within a year, were apparently important and resulted in higher zooplankton abundance

A novel sexual system in male gametophytes of <i>Laminaria pallida</i> (Phaeophyceae)

Brown algae (Phaeophyceae) exhibit a wide diversity of sexual systems, reproductive modes and life histories. The evolution of this diversity has often involved transitions between sexual systems, which may influence genetic diversity and diversification, and phenotypic evolution. This study reports a novel sexual system in kelp. We identified male gametophyte strains of Laminaria pallida that, despite presenting morphological features typical of a male, developed both antheridia and egg-like structures, which suggest an incomplete suppression of femaleness during sexual determination of gametophytes. The sperm released by these variant male gametophytes successfully fertilize eggs produced by female gametophytes, developing into sporophytes with normal morphologies. However, morphologically abnormal sporophytic offspring were formed in isolated variant male gametophytes, indicating that the egg-like structures were not successfully self-fertilized by sperm. The causes of the unsuccessful intragametophytic selfing are unknown, but absence of pheromone production by the egg-like structures is a hypothesis suggested by available evidence. Partial co-sexuality is clearly inherited, as all male gametophyte strains descended from the same sporophyte developed egg-like structures. Further investigation into the genetics and maturation of male partheno-sporophytes will help to estimate the potential effects of this mechanism on natural populations. Morphologically typical male gametophytes in Laminaria pallida developed both antheridia and egg-like structures.Male sexual reproductive ability was retained by partially co-sexual L. pallida gametophytes.Partial co-sexuality appears to be heritable but varies between L. pallida individuals. Morphologically typical male gametophytes in Laminaria pallida developed both antheridia and egg-like structures. Male sexual reproductive ability was retained by partially co-sexual L. pallida gametophytes. Partial co-sexuality appears to be heritable but varies between L. pallida individuals.</p

Abundance (no. m⁻²) and distribution of a) total zooplankton, b) total copepods, c) cyclopoid copepods and d) calanoid copepods shown for each year along the transect.

<p>Abundance (no. m⁻²) and distribution of a) total zooplankton, b) total copepods, c) cyclopoid copepods and d) calanoid copepods shown for each year along the transect.</p

Monthly means (±SD) of a) temperature at 10 m, b) chlorophyll <i>a</i>, c) total zooplankton, d) total copepods, e) calanoid copepods, f) <i>Calanoides carinatus</i>, g) <i>Metridia lucens</i> and h) <i>Nannocalanus minor</i>. Note different scales.

<p>Monthly means (±SD) of a) temperature at 10 m, b) chlorophyll <i>a</i>, c) total zooplankton, d) total copepods, e) calanoid copepods, f) <i>Calanoides carinatus</i>, g) <i>Metridia lucens</i> and h) <i>Nannocalanus minor</i>. Note different scales.</p

Abundances (no. m⁻²) of <i>Calanoides carinatus</i> in relation to chlorophyll <i>a</i> concentration and temperature at 10 m depth.

<p>The area of each circle is proportional to the abundance shown in the legend.</p