Genome-wide association studies of COVID-19: Connecting the dots.

Genome-wide association studies (GWASs) are a research approach used to identify genetic variants associated with common diseases, like COVID-19. The lead genetic variants (n = 41) reported by the eleven largest COVID-19 GWASs are mapped to 22 different chromosomal regions. The loci 3q21.31 (LZTFL1 and chemokine receptor genes) and 9q34.2 (ABO), associated with disease severity and susceptibility to infection, respectively, were the most replicated findings across studies. Genes involved with mucociliary clearance (CEP97, FOXP4), viral-entry (ACE2, SLC6A20) and mucosal immunity (MIR6891) are associated with the risk of SARS-CoV-2 infection while genes of antiviral immune response (IFNAR2, OAS1), leukocyte trafficking (CCR9, CXCR6) and lung injury (DPP9, NOTCH4) are associated with severe disease. The biological processes underlying the risk of infection occur prominently, but not exclusively, in the upper airways whereas the severe COVID-19-associated processes in alveolar-capillary interface. The COVID-19 GWASs has unraveled key genetic mechanisms of SARS-CoV-2 pathogenesis, although the genetic basis of other COVID-19 related phenotypes (long COVID and neurological impairment) remains to be elucidated.

Plasma angiotensin II levels in women with severe preeclampsia under magnesium sulfate regimen.

The role of Renin-Angiotensin-System (RAS) in the pathogenesis of preeclampsia and eclampsia is still unclear. Our aim was to investigate plasma angiotensin II concentration [Ang II] in women with normotensive pregnancies (NP, n = 22) and severe preeclampsia in use of magnesium sulfate (SPE, n = 29). Despite no difference between the groups (SPE: 47.8 pg/ml vs NP: 39.7 pg/ml, p = 0.195), lower maternal age (p = 0.007) and primigravida (p = 0.028) were associated with lower [Ang II]. Plasma [Ang II] increased over the 24 h of magnesium sulfate administration (r = 0.48, p = 0.009). Our findings suggest that RAS may be involved with the mechanism of magnesium protection against eclamptic seizure.

Report of a Father With Congenital Bilateral Absence of the Vas Deferens Fathering a Child With Beare-Stevenson Syndrome.

BACKGROUND: Apert, Pfeiffer, and Crouzon syndromes are autosomal dominant diseases characterized by craniosynostosis. They are paternal age effect disorders. The association between paternal age and Beare-Stevenson syndrome (BSS), a very rare and severe craniosynostosis, is uncertain. Gain-of-function mutations in FGFR2 become progressively enriched in testes as men age and were shown to cause these syndromes. CASE REPORT: Here, we describe a child affected with BSS, whose father was 36 years old and had congenital bilateral absence of the vas deferens (CBAVD). The child was heterozygous for the pathogenic FGFR2 variant c.1124A > G p.Tyr375Cys. By reviewing the literature, we found that BSS fathers are older than BSS mothers (mean age in years: 39 ± 10 vs 30 ± 6, p = 0.006). Male age greater than 34 years and CBAVD are both factors associated with poor spermogram parameters, which may represent an additional selective pressure to sperm carrying FGFR2 gain-of-function mutations. CONCLUSION: These findings are consistent with the hypothesis that BSS is a paternal-origin genetic disorder. Further experimental studies would be needed to confirm this hypothesis.

Polymorphism in Mitochondrial Group I Introns among Cryptococcus neoformans and Cryptococcus gattii Genotypes and Its Association with Drug Susceptibility.

Cryptococcosis, one of the most important systemic mycosis in the world, is caused by different genotypes of Cryptococcus neoformans and Cryptococcus gattii, which differ in their ecology, epidemiology, and antifungal susceptibility. Therefore, the search for new molecular markers for genotyping, pathogenicity and drug susceptibility is necessary. Group I introns fulfill the requisites for such task because (i) they are polymorphic sequences; (ii) their self-splicing is inhibited by some drugs; and (iii) their correct splicing under parasitic conditions is indispensable for pathogen survival. Here, we investigated the presence of group I introns in the mitochondrial LSU rRNA gene in 77 Cryptococcus isolates and its possible relation to drug susceptibility. Sequencing revealed two new introns in the LSU rRNA gene. All the introns showed high sequence similarity to other mitochondrial introns from distinct fungi, supporting the hypothesis of an ancient non-allelic invasion. Intron presence was statistically associated with those genotypes reported to be less pathogenic (p < 0.001). Further virulence assays are needed to confirm this finding. In addition, in vitro antifungal tests indicated that the presence of LSU rRNA introns may influence the minimum inhibitory concentration (MIC) of amphotericin B and 5-fluorocytosine. These findings point to group I introns in the mitochondrial genome of Cryptococcus as potential molecular markers for antifungal resistance, as well as therapeutic targets.

Characterization of Soybean Genetically Modified for Drought Tolerance in Field Conditions.

Drought is one of the most stressful environmental factor causing yield and economic losses in many soybean-producing regions. In the last decades, transcription factors (TFs) are being used to develop genetically modified plants more tolerant to abiotic stresses. Dehydration responsive element binding (DREB) and ABA-responsive element-binding (AREB) TFs were introduced in soybean showing improved drought tolerance, under controlled conditions. However, these results may not be representative of the way in which plants behave over the entire season in the real field situation. Thus, the objectives of this study were to analyze agronomical traits and physiological parameters of AtDREB1A (1Ab58), AtDREB2CA (1Bb2193), and AtAREB1 (1Ea2939) GM lines under irrigated (IRR) and non-irrigated (NIRR) conditions in a field experiment, over two crop seasons and quantify transgene and drought-responsive genes expression. Results from season 2013/2014 revealed that line 1Ea2939 showed higher intrinsic water use and leaf area index. Lines 1Ab58 and 1Bb2193 showed a similar behavior to wild-type plants in relation to chlorophyll content. Oil and protein contents were not affected in transgenic lines in NIRR conditions. Lodging, due to plentiful rain, impaired yield from the 1Ea2939 line in IRR conditions. qPCR results confirmed the expression of the inserted TFs and drought-responsive endogenous genes. No differences were identified in the field experiment performed in crop season 2014/2015, probably due to the optimum rainfall volume during the cycle. These field screenings showed promising results for drought tolerance. However, additional studies are needed in further crop seasons and other sites to better characterize how these plants may outperform the WT under field water deficit.

Identifying Leprosy and Those at Risk of Developing Leprosy by Detection of Antibodies against LID-1 and LID-NDO.

Leprosy is caused by Mycobacterium leprae infection and remains a major public health problem in many areas of the world. Challenges to its timely diagnosis result in delay in treatment, which is usually associated with severe disability. Although phenolic glycolipid (PGL)-I has been reported as auxiliary diagnostic tool, currently there is no serological assay routinely used in leprosy diagnosis. The aim of this study was to evaluate the effectiveness of two related reagents, LID-1 and LID-NDO, for the detection of M. leprae infection. Sera from 98 leprosy patients, 365 household contacts (HHC) and 98 endemic controls from Rio Grande do Norte, Brazil, were evaluated. A subgroup of the HHC living in a hyperendemic area was followed for 7-10 years. Antigen-specific antibody responses were highest in multibacillary (MB) at the lepromatous pole (LL/BL) and lowest in paucibacillary (PB) at the tuberculoid pole (TT/BT). A positive correlation for both anti-LID-1 and anti-LID-NDO antibodies was found with bacterial burden (LID-1, r = 0.84, p<0.001; LID-NDO, r = 0.82, p<0.001), with higher sensitivity than bacilloscopy. According to Receiver Operating Curve, LID-1 and LID-NDO performed similarly. The sensitivity for MB cases was 89% for LID-1 and 95% for LID-NDO; the specificity was 96% for LID-1 and 88% for LID-NDO. Of the 332 HHC that were followed, 12 (3.6%) were diagnosed with leprosy in a median time of 31 (3-79) months after recruitment. A linear generalized model using LID-1 or LID-NDO as a predictor estimated that 8.3% and 10.4% of the HHC would become a leprosy case, respectively. Together, our findings support a role for the LID-1 and LID-NDO antigens in diagnosing MB leprosy and identifying people at greater risk of developing clinical disease. These assays have the potential to improve the diagnostic capacity at local health centers and aid development of strategies for the eventual control and elimination of leprosy from endemic areas.

Family history of hypertension as an important risk factor for the development of severe preeclampsia.

OBJECTIVE: To determine the risk of preeclampsia in a population with respect to maternal and sister histories of chronic hypertension, preeclampsia and eclampsia. DESIGN: A case-control study of severe preeclampsia. SETTING: Maternity hospital in Natal, Brazil. PARTICIPANTS: A total of 412 subjects were enrolled, 148 cases and 264 controls. MAIN OUTCOME MEASURES: Personal and familial histories of hypertensive disorders. Odds ratio estimates of preeclampsia with respect to family history of hypertensive diseases. RESULTS: Women with a history of hypertensive disorders were more frequent in the case group (p = 0.001). Women whose mothers had a history of hypertension (p = 0.003), preeclampsia (p = 0.007) or eclampsia (p = 0.038) were at increased risk of severe preeclampsia. The risk of preeclampsia was greater when the woman had a sister with a history of hypertension (OR 2.60, 95% CI 1.60-4.21, p < 0.001), preeclampsia (OR 2.33, 95% CI 1.58-3.45, p < 0.001), or eclampsia (OR 2.57, 95% CI 1.28-5.16, p = 0.008). The risk of preeclampsia was also higher for women who had both a mother and sister with a history of hypertension (OR 3.65, 95% CI 1.65-8.09, p = 0.001). CONCLUSIONS: A family history of hypertensive disorders increased the risk of eclampsia and hemolysis elevated liver enzymes and low platelet (HELLP) syndrome in a Brazilian population.