Immunogenic Potential of the Mediterranean Fever Gene in Patients with Coronavirus Disease: A Cross-Sectional Study.

Background: In December 2019, an outbreak of pneumonia caused by the novel coronavirus disease 2019 (COVID-19) became a pandemic and caused a global health crisis. This study evaluates the immunogenic potential of the Mediterranean fever (MEFV) gene in patients with COVID-19. Methods: A cross-sectional study was conducted from March to April 2020 in various COVID-19 referral centers in Ardabil, Iran. Blood samples of 50 hospitalized patients with confirmed COVID-19 were evaluated for MEFV gene mutation using the amplification refractory mutation system polymerase chain reaction (ARMS-PCR) and Sanger sequencing. Statistical analysis was performed using SPSS software, version 22.0. Results: Mutations of the MEFV gene were found in 6 (12%) of the patients. All mutations were heterozygous, and no homozygous or compound heterozygous forms were detected. The total mutant allele frequency was 6% and the carrier rate was 12%. The most common allele of the MEFV variant was E148Q, detected in 3 (6%) patients. No mutant variant of the MEFV gene was detected in deceased patients. None of the mutation carriers had familial Mediterranean fever (FMF) symptoms or a family history of FMF. Conclusion: MEFV gene mutations may have immunogenic potential in patients with COVID-19. A preprint version of this article has already been published at https://www.researchsquare.com/article/rs-69373/latest.pdf.

Multifactorial Rare Diseases: Can Uncertainty Analysis Bring Added Value to the Search for Risk Factors and Etiopathogenesis?

Uncertainty analysis is the process of identifying limitations in knowledge and evaluating their implications for scientific conclusions. Uncertainty analysis is a stable component of risk assessment and is increasingly used in decision making on complex health issues. Uncertainties should be identified in a structured way and prioritized according to their likely impact on the outcome of scientific conclusions. Uncertainty is inherent to the rare diseases (RD) area, where research and healthcare have to cope with knowledge gaps due to the rarity of the conditions; yet a systematic approach toward uncertainties is not usually undertaken. The uncertainty issue is particularly relevant to multifactorial RD, whose etiopathogenesis involves environmental factors and genetic predisposition. Three case studies are presented: the newly recognized acute multisystem inflammatory syndrome in children and adolescents associated with SARS-CoV-2 infection; the assessment of risk factors for neural tube defects; and the genotype-phenotype correlation in familial Mediterranean fever. Each case study proposes the initial identification of the main epistemic and sampling uncertainties and their impacts. Uncertainty analysis in RD may present aspects similar to those encountered when conducting risk assessment in data-poor scenarios; therefore, approaches such as expert knowledge elicitation may be considered. The RD community has a main strength in managing uncertainty, as it proactively develops stakeholder involvement, data sharing and open science. The open science approaches can be profitably integrated by structured uncertainty analysis, especially when dealing with multifactorial RD involving environmental and genetic risk factors.

Familial Mediterranean Fever and COVID-19: Friends or Foes?

Familial Mediterranean Fever (FMF) and COVID-19 show a remarkable overlap of clinical symptoms and similar laboratory findings. Both are characterized by fever, abdominal/chest pain, elevation of C-reactive protein, and leukocytosis. In addition, colchicine and IL-1 inhibitors treatments that are effective in controlling inflammation in FMF patients have recently been proposed for off-label use in COVID-19 patients. Thus, FMF may resemble a milder recapitulation of the cytokine storm that is a hallmark of COVID-19 patients progressing to severe disease. We analyzed the sequence of the MEFV-encoded Pyrin protein - whose mutations cause FMF- in mammals, bats and pangolin. Intriguingly, although Pyrin is extremely conserved in species that are considered either a reservoir or intermediate hosts for SARS-CoV-2, some of the most common FMF-causing variants in humans are present as wildtype residues in these species. We propose that in humans, Pyrin may have evolved to fight highly pathogenic infections.