RESUMEN
BACKGROUND: Given the sparse data on the renin-angiotensin system (RAS) and its biological effector molecules ACE1 and ACE2 in pediatric COVID-19 cases, we investigated whether the ACE1 insertion/deletion (I/D) polymorphism could be a genetic marker for susceptibility to COVID-19 in Egyptian children and adolescents. METHODS: This was a case-control study included four hundred sixty patients diagnosed with COVID-19, and 460 well-matched healthy control children and adolescents. The I/D polymorphism (rs1799752) in the ACE1 gene was genotyped by polymerase chain reaction (PCR), meanwhile the ACE serum concentrations were assessed by ELISA. RESULTS: The ACE1 D/D genotype and Deletion allele were significantly more represented in patients with COVID-19 compared to the control group (55% vs. 28%; OR = 2.4; [95% CI: 1.46-3.95]; for the DD genotype; P = 0.002) and (68% vs. 52.5%; OR: 1.93; [95% CI: 1.49-2.5] for the D allele; P = 0.032). The presence of ACE1 D/D genotype was an independent risk factor for severe COVID-19 among studied patients (adjusted OR: 2.6; [95% CI: 1.6-9.7]; P < 0.001. CONCLUSIONS: The ACE1 insertion/deletion polymorphism may confer susceptibility to SARS-CoV-2 infection in Egyptian children and adolescents. IMPACT: Recent studies suggested a crucial role of renin-angiotensin system and its biological effector molecules ACE1 and ACE2 in the pathogenesis and progression of COVID-19. To our knowledge, ours is the first study to investigate the association of ACE1 I/D polymorphism and susceptibility to COVID-19 in Caucasian children and adolescents. The presence of the ACE1 D/D genotype or ACE1 Deletion allele may confer susceptibility to SARS-CoV-2 infection and being associated with higher ACE serum levels; may constitute independent risk factors for severe COVID-19. The ACE1 I/D genotyping help design further clinical trials reconsidering RAS-pathway antagonists to achieve more efficient targeted therapies.
RESUMEN
BACKGROUND: Given the sparse data on vitamin D status in pediatric COVID-19, we investigated whether vitamin D deficiency could be a risk factor for susceptibility to COVID-19 in Egyptian children and adolescents. We also investigated whether vitamin D receptor (VDR) FokI polymorphism could be a genetic marker for COVID-19 susceptibility. METHODS: One hundred and eighty patients diagnosed to have COVID-19 and 200 matched control children and adolescents were recruited. Patients were laboratory confirmed as SARS-CoV-2 positive by real-time RT-PCR. All participants were genotyped for VDR Fok1 polymorphism by RT-PCR. Vitamin D status was defined as sufficient for serum 25(OH) D at least 30 ng/mL, insufficient at 21-29 ng/mL, deficient at <20 ng/mL. RESULTS: Ninety-four patients (52%) had low vitamin D levels with 74 (41%) being deficient and 20 (11%) had vitamin D insufficiency. Vitamin D deficiency was associated with 2.6-fold increased risk for COVID-19 (OR = 2.6; [95% CI 1.96-4.9]; P = 0.002. The FokI FF genotype was significantly more represented in patients compared to control group (OR = 4.05; [95% CI: 1.95-8.55]; P < 0.001). CONCLUSIONS: Vitamin D deficiency and VDR Fok I polymorphism may constitute independent risk factors for susceptibility to COVID-19 in Egyptian children and adolescents. IMPACT: Vitamin D deficiency could be a modifiable risk factor for COVID-19 in children and adolescents because of its immune-modulatory action. To our knowledge, ours is the first such study to investigate the VDR Fok I polymorphism in Caucasian children and adolescents with COVID-19. Vitamin D deficiency and the VDR Fok I polymorphism may constitute independent risk factors for susceptibility to COVID-19 in Egyptian children and adolescents. Clinical trials should be urgently conducted to test for causality and to evaluate the efficacy of vitamin D supplementation for prophylaxis and treatment of COVID-19 taking into account the VDR polymorphisms.