Understanding the interaction between humans and mosquitoes is a critical area of study due to the phenomenal burdens on public health from mosquito-transmitted diseases. In this study, we conducted the first genome-wide association studies (GWAS) of self-reported mosquito bite reaction size (n = 84,724), itchiness caused by bites (n = 69,057), and perceived attractiveness to mosquitoes (n = 16,576). In total, 15 independent significant (P < 5×10−8) associations were identified. These loci were enriched for immunity-related genes that are involved in multiple cytokine signalling pathways. We also detected suggestive enrichment of these loci in enhancer regions that are active in stimulated T-cells, as well as within loci previously identified as controlling central memory T-cell levels. Egger regression analysis between the traits suggests that perception of itchiness and attractiveness to mosquitoes is driven, at least in part, by the genetic determinants of bite reaction size.Our findings illustrate the complex genetic and immunological landscapes underpinning human interactions with mosquitoes.

Objective. To investigate the role of PF-06650833, a highly potent and selective small-molecule inhibitor of interleukin-1-associated kinase 4 (IRAK4), in autoimmune pathophysiology in vitro, in vivo, and in the clinical setting.Methods. Rheumatoid arthritis (RA) inflammatory pathophysiology was modeled in vitro through 1) stimulation of primary human macrophages with anti-citrullinated protein antibody immune complexes (ICs), 2) RA fibroblast-like synoviocyte (FLS) cultures stimulated with Toll-like receptor (TLR) ligands, as well as 3) additional human primary cell cocultures exposed to inflammatory stimuli. Systemic lupus erythematosus (SLE) pathophysiology was simulated in human neutrophils, dendritic cells, B cells, and peripheral blood mononuclear cells stimulated with TLR ligands and SLE patient ICs. PF-06650833 was evaluated in vivo in the rat collagen-induced arthritis (CIA) model and the mouse pristane-induced and MRL/lpr models of lupus. Finally, RNA sequencing data generated with whole blood samples from a phase I multiple-ascending-dose clinical trial of PF-06650833 were used to test in vivo human pharmacology.Results. In vitro, PF-06650833 inhibited human primary cell inflammatory responses to physiologically relevant stimuli generated with RA and SLE patient plasma. In vivo, PF-06650833 reduced circulating autoantibody levels in the pristane-induced and MRL/lpr murine models of lupus and protected against CIA in rats. In a phase I clinical trial (NCT02485769), PF-06650833 demonstrated in vivo pharmacologic action pertinent to SLE by reducing whole blood interferon gene signature expression in healthy volunteers.Conclusion. These data demonstrate that inhibition of IRAK4 kinase activity can reduce levels of inflammation markers in humans and provide confidence in the rationale for clinical development of IRAK4 inhibitors for rheumatologic indications.ClinicalTrials.gov identifier: NCT02485769.

Study Design Model-independent linkage analysis and tests of association were performed for 22 single nucleotide polymorphisms (SNPs) in the CHD7 gene in 244 families of European descent with familial idiopathic scoliosis (FIS). Objective To replicate an association between FIS and the CHD7 gene on 8q12.2 in an independent sample of families of European descent. Summary of Background Data The CHD7 gene on chromosome 8, responsible for the CHARGE syndrome, was previously associated with FIS in an independent study that included 52 families of European descent. Methods Model-independent linkage analysis and intra-familial tests of association were performed on the degree of lateral curvature considered as a qualitative trait (with thresholds of ≥10°, ≥15°, ≥20° and ≥30°) and as a quantitative trait (degree of lateral curvature). Results from the tests of associations from this study and the previous study were combined in a weighted meta-analysis. Results No significant results (P< 0.01) were found for linkage analysis or tests of association between genetic variants of the CHD7 and FIS in this study sample, failing to replicate the findings from the previous study. Furthermore, no significant results (P< 0.01) were found from meta-analysis of the results from the tests of association from this sample and from the previous sample. Conclusion No association between the 22 genotyped SNPs in the CHD7 gene and FIS within this study sample was found, failing to replicate the earlier findings. Further investigation of the CHD7 gene and its potential association to FIS may be required.

Background Defining clinical phenotypes provides opportunities for new diagnostics and may provide insights into early intervention and disease prevention. There is increasing evidence that patient-derived health data may contain information that complements traditional methods of clinical phenotyping. The utility of these data for defining meaningful phenotypic groups is of great interest because social media and online resources make it possible to query large cohorts of patients with health conditions. Methods We evaluated the degree to which patient-reported categorical data is useful for discovering subclinical phenotypes and evaluated its utility for discovering new measures of disease severity, treatment response and genetic architecture. Specifically, we examined the responses of 1961 patients with inflammatory bowel disease to questionnaires in search of sub-phenotypes. We applied machine learning methods to identify novel subtypes of Crohn’s disease and studied their associations with drug responses. Results Using the patients’ self-reported information, we identified two subpopulations of Crohn’s disease; these subpopulations differ in disease severity, associations with smoking, and genetic transmission patterns. We also identified distinct features of drug response for the two Crohn’s disease subtypes. These subtypes show a trend towards differential genotype signatures. Conclusion Our findings suggest that patient-defined data can have unplanned utility for defining disease subtypes and may be useful for guiding treatment approaches.