Anti-RORa Polyclonal Antibody Knockout Validated

Abnormalities in circadian rhythms play an important role in the pathogenesis of bipolar disorders (BD). Previous genetic studies have reported discrepant results regarding associations between circadian genes and susceptibility to BD. Furthermore, plausible behavioral consequences of at-risk variants remain unclear since there is a paucity of correlates with phenotypic biomarkers such as chronotypes. Here, we combined association studies with a genotype/phenotype correlation in order to determine which circadian genes variants may be associated with the circadian phenotypes observed in patients with BD. First, we compared the allele frequencies of 353 single nucleotide polymorphisms spanning 21 circadian genes in two independent samples of patients with BD and controls. The meta-analysis combining both samples showed a significant association between rs774045 in TIMELESS (OR = 1.49 95%CI[1.18-1.88]; p = 0.0008) and rs782931 in RORA (OR = 1.31 95%CI[1.12-1.54]; p = 0.0006) and BD. Then we used a "reverse phenotyping approach'' to look for association between these two polymorphisms and circadian phenotypes in a subsample of patients and controls. We found that rs774045 was associated with eveningness (p = 0.04) and languid circadian type (p = 0.01), whereas rs782931 was associated with rigid circadian type (p = 0.01). Altogether, these findings suggest that these variants in the TIMELESS and RORA genes may confer susceptibility to BD and impact on circadian phenotypes in carriers who thus had lower ability to properly adapt to external cues.

Retinoid acid receptor-related Orphan Receptor Alpha (RORA) was recently identified as a susceptibility gene for asthma in a genome-wide association study. To investigate the impact of RORA on asthma susceptibility, we performed a genetic association study between RORA single nucleotide polymorphisms (SNPs) in the vicinity of the asthma-associated SNP (rs11071559) and asthma-related traits. Because the regulatory region of a previously implicated asthma susceptibility gene, Neuropeptide S receptor 1 (NPSR1), has predicted elements for RORA binding, we hypothesized that RORA may interact biologically and genetically with NPSR1. 37 RORA SNPs and eight NPSR1 SNPs were genotyped in the Swedish birth cohort BAMSE (2033 children) and the European cross-sectional PARSIFAL study (1120 children). Seven RORA SNPs confined into a 49 kb region were significantly associated with physician-diagnosed childhood asthma. The most significant association with rs7164773 (T/C) was driven by the CC genotype in asthma cases (OR = 2.0, 95% CI 1.36-2.93, p = 0.0003 in BAMSE; and 1.61, 1.18-2.19, p = 0.002 in the combined BAMSE-PARSIFAL datasets, respectively), and strikingly, the risk effect was dependent on the Gln344Arg mutation in NPSR1. In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. Over-expression of RORA decreased NPSR1 promoter activity further suggesting a regulatory loop between these genes. In addition, Rora mRNA expression was lower in the lung tissue of Npsr1 deficient mice compared to wildtype littermates during the early hours of the light period. We conclude that RORA SNPs are associated with childhood asthma and show epistasis with NPSR1, and the interaction between RORA and NPSR1 may be of biological relevance. Combinations of common susceptibility alleles and less common functional polymorphisms may modify the joint risk effects on asthma susceptibility.