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Context Adrenarche reflects the developmental growth of the adrenal zona reticularis, which produces increasing adrenal androgen secretion (eg, dehydroepiandrosterone [DHEA]/dehydroepiandrosterone sulfate [DHEAS]) from approximately age 5 to 15 years. Objective We hypothesized that the study of the genetic determinants associated with variations in serum DHEAS during adrenarche might detect genetic variants influencing the rate or timing of this process. Methods Genome-wide genotyping was performed in participants of the Chilean pediatric Growth and Obesity Chilean Cohort Study (GOCS) cohort (n = 788). We evaluated the genetic determinants of DHEAS levels at the genome-wide level and in targeted genes associated with steroidogenesis. To corroborate our findings, we evaluated a polygenic risk score (PRS) for age at pubarche, based on the discovered variants, in children from the same cohort. Results We identified one significant variant at the genome-wide level in the full cohort, close to the GALR1 gene (P = 3.81 × 10–8). In addition, variants suggestive of association (P Conclusion Our results disclose one variant associated with DHEAS concentrations at the level of genome-wide association study significance, and several variants with a suggestive association that may be involved in the genetic regulation of adrenarche.

BackgroundThe recent COVID-19 pandemic has posed an unprecedented challenge to laboratory diagnosis, based on the amplification of SARS-CoV-2 RNA. With global contagion figures exceeding 4 million persons, the shortage of reagents for RNA extraction represents a bottleneck for testing globally. We present the validation results for a RT-qPCR protocol without prior RNA extraction. Because of its simplicity, this protocol is suitable for widespread application in resource-limited settings.MethodsOptimal protocol was selected by comparing RT-qPCR performance under a set of thermal (65°, 70°, and 95° for 5, 10, and 30 minutes) and amplification conditions (3 or 3,5 uL loading volume; 2 commercial RT-qPCR kits with limit of detection below 10 copies/sample) in nasopharyngeal swabs stored at 4°C in sterile Weise’s buffer pH 7.2. The selected protocol was evaluated for classification concordance with the standard protocol (automated RNA extraction) in 130 routine samples and in 50 historical samples with Cq values near to the clinical decision limit.ResultsOptimal selected conditions were: Thermal shock at 70° C for 10 minutes, loading 3.5 ul in the RT-qPCR. Prospective evaluation in 130 routine samples showed 100% classification concordance with the standard protocol. The evaluation in historical samples, selected because their Cqs were at the clinical decision limit, showed 94% concordance with our confirmatory-gold standard which includes manual RNA extraction.ConclusionsThese results validate the use of this direct RT-qPCR protocol as a safe alternative for SARS CoV-2 diagnosis in case of a shortage of reagents for RNA extraction, with minimal clinical impact.

Genetic testing for monogenic diabetes, essential for accurate diagnosis and appropriate treatment is underutilized. Obstacles include clinical overlap with type 1 and type 2 diabetes and difficulty distinguishing clinically significant (pathogenic/likely pathogenic; P/LP) from normal (benign/likely benign; B/LB) variation. The ClinGen Monogenic Diabetes Expert Panel (MDEP) was formed to adapt American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) variant interpretation guidelines to monogenic diabetes genes and enable depositing of expert panel variant reviews into ClinVar, a public database relating gene variants to phenotypes. MDEP includes endocrinologists, laboratory directors, genetic counselors, medical geneticists, clinical scientists and researchers from 37 academic and commercial institutions, allowing the panel to benefit from multiple expert perspectives and pooling of case-level data. Currently, MDEP is focusing on the three most commonly implicated monogenic diabetes genes: GCK, HNF1A and HNF4A. MDEP generated gene-specific modifications and/or strength adjustments to existing rules to provide guidance for the use of evidence, including molecular, phenotypic, segregation, functional, and minor allele frequency data. Our guidelines have so far been tested on 98 HNF1A variants, 15 HNF4A variants and 22 GCK variants selected from ClinVar and the literature. Fourteen of 31 variants of uncertain significance (VUS) in ClinVar were re-classified: nine to P/LP (enabling diagnosis and treatment) and five to B/LB (reducing ambiguity). Six LP variants and one LB variant from ClinVar were re-classified to VUS (stimulating further surveillance). MDEP’s work will improve accuracy, standardization and concordance of variant interpretation for monogenic diabetes and support wider implementation of precision medicine in diabetes. Disclosure H. Zhang: None. K.A. Maloney: None. F. Barbetti: Consultant; Self; Amring. S.W. Greeley: None. J.L.T. Kettunen: None. J.P. Miranda: None. U.L. Mirshahi: None. J. Molnes: None. R. Murphy: None. R.N. Naylor: None. R.E. Pakyz: None. L.H. Philipson: None. S. Prudente: None. T. Tuomi: None. M. Udler: None. K. Colclough: None. L. Jeng: None. T.I. Pollin: None. Funding National Institutes of Health (5U24HD093486, R01DK104942, P30DK020595 )

The main environmental risk factor associated with the development of Crohn's disease (CD) is cigarette smoking. Although the mechanism is still unknown, some studies have shown that cigarette exposure affects the intestinal barrier of the small bowel. Among the factors that may be involved in this process are Paneth cells. These specialized epithelial cells are located into the small intestine, and they are able to secrete antimicrobial peptides, having an essential role in the control of the growth of microorganisms. Alterations in its function are associated with inflammatory processes, such as CD. To study how cigarette components impact ileum homeostasis and Paneth cells integrity, we used intragastric administration of cigarette smoke condensate (CSC) in mice. Our results showed that inflammation was triggered after mucosal exposure of CSC, which induced particular alterations in Paneth cells granules, antimicrobial peptide production, and a reduction of bactericidal capacity. In fact, exposure to CSC generated an imbalance in the fecal bacterial population and increased the susceptibility of mice to develop ileal damage in response to bacterial infection. Moreover, our results obtained in mice unable to produce interleukin 10 (IL-10−/− mice) suggest that CSC treatment can induce a symptomatic enterocolitis with a pathological inflammation in genetically susceptible individuals.