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Research indicates that rates of alcohol use and alcohol consequences are higher among LGBQ emerging adults (EAs; ages 18-25) than among their heterosexual counterparts and this is partly due to experiences of sexual orientation-based discrimination. To date, however, there is limited research on factors that mitigate against increased alcohol outcomes among LGBQ EAs. The purpose of the current study was to examine the buffering effects of LGBQ social identity components (ingroup ties, centrality, ingroup affect) on the relationship between two types of discrimination (homonegative microaggressions and discrimination violence) and alcohol use and consequences. A community-based sample of 252 LGBQ EAs completed an online survey. There was a significant moderating effect for ingroup ties and ingroup affect where the relationship between homonegative microaggressions and alcohol use and consequences was lower for those higher on these social identity components; there was no moderating effect of any social identity component on the association between discrimination violence and either alcohol outcome. Social identity factors strongly affiliated with the LGBTQ community act as both a buffer in the face of subtle forms of discrimination and, more generally, a way to counteract the typical trajectory of increased alcohol use and consequences among LGBQ EAs.

The neural crest, an embryonic stem-cell population, is a vertebrate innovation that has been proposed to be a key component of the 'new head', which imbued vertebrates with predatory behaviour.sup.1,2. Here, to investigate how the evolution of neural crest cells affected the vertebrate body plan, we examined the molecular circuits that control neural crest development along the anteroposterior axis of a jawless vertebrate, the sea lamprey. Gene expression analysis showed that the cranial subpopulation of the neural crest of the lamprey lacks most components of a transcriptional circuit that is specific to the cranial neural crest in amniotes and confers the ability to form craniofacial cartilage onto non-cranial neural crest subpopulations.sup.3. Consistent with this, hierarchical clustering analysis revealed that the transcriptional profile of the lamprey cranial neural crest is more similar to the trunk neural crest of amniotes. Notably, analysis of the cranial neural crest in little skate and zebrafish embryos demonstrated that the transcriptional circuit that is specific to the cranial neural crest emerged via the gradual addition of network components to the neural crest of gnathostomes, which subsequently became restricted to the cephalic region. Our results indicate that the ancestral neural crest at the base of the vertebrate lineage possessed a trunk-like identity. We propose that the emergence of the cranial neural crest, by progressive assembly of an axial-specific regulatory circuit, allowed the elaboration of the new head during vertebrate evolution. Analysis of gene expression in the neural crest of vertebrate embryos supports the idea that gene regulatory circuits that define the cranial neural crest evolved gradually from a more trunk-like identity., Author(s): Megan L. Martik [sup.1] , Shashank Gandhi [sup.1] , Benjamin R. Uy [sup.1] , J. Andrew Gillis [sup.2] [sup.3] , Stephen A. Green [sup.1] , Marcos Simoes-Costa [sup.4] , [...]