ABCA3 and LZTFL1 Polymorphisms and Risk of COVID-19 in the Czech Population

Potential associations of selected polymorphic genetic variants with COVID-19 disease susceptibility and severity

In this study, we analyzed the potential associations of selected laboratory and anamnestic parameters, as well as 12 genetic polymorphisms (SNPs), with clinical COVID-19 occurrence and severity in 869 hospitalized patients. The SNPs analyzed by qPCR were selected based on population-wide genetic (GWAS) data previously indicating association with the severity of COVID-19, and additional SNPs that have been shown to be important in cellular processes were also examined. We confirmed the associations of COVID-19 with pre-existing diabetes and found an unexpected association between less severe disease and the loss of smell and taste. Regarding the genetic polymorphisms, a higher allele frequency of the LZTFL1 and IFNAR2 minor variants significantly correlated with greater COVID-19 disease susceptibility (hospitalization) and severity, and a similar tendency was observed for the RAVER1 and the MUC5B variants. Interestingly, the ATP2B4 minor haplotype, protecting against malaria, correlated with an increased disease susceptibility, while in diabetic patients disease susceptibility was lower in the presence of a reduced-function ABCG2 transporter variant. Our current results, which should be reinforced by larger studies, indicate that together with laboratory and anamnestic parameters, genetic polymorphisms may have predictive value for the clinical occurrence and severity of COVID-19.

Increased prevalence of the COVID-19 associated Neanderthal mutations in the Central European Roma population

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and subsequent COVID-19 has spread world-wide and become pandemic with about 7 million deaths reported so far. Interethnic variability of the disease has been described, but a significant part of the differences remain unexplained and may be attributable to genetic factors.

AIM

To analyse genetic factors potentially influencing COVID-19 susceptibility and severity in European Roma minority.

SUBJECTS AND METHODS

Two genetic determinants, within OAS-1 (2-prime,5-prime-oligoadenylate synthetase 1, a key protein in the defence against viral infection; it activates RNases that degrade viral RNAs; rs4767027 has been analysed) and LZTFL1 (leucine zipper transcription factor-like 1, expressed in the lung respiratory epithelium; rs35044562 has been analysed) genes were screened in a population-sample of Czech Roma (N = 302) and majority population (N = 2,559).

RESULTS

For both polymorphisms, Roma subjects were more likely carriers of at least one risky allele for both rs4767027-C (p < 0.001) and rs35044562-G (p < 0.00001) polymorphism. There were only 5.3% Roma subjects without at least one risky allele in comparison with 10.1% in the majority population (p < 0.01).

CONCLUSIONS

It is possible that different genetic background plays an important role in increased prevalence of COVID-19 in the Roma minority.

Possible effect of OAS1 and TMPRSS6 but not DPP4 and ZNF335 polymorphisms on COVID-19 severity in the Czech population

OBJECTIVES

The acute respiratory syndrome, known as COVID-19, is characterised by high morbidity and increased mortality. Genetic factors may partially explain the differences in susceptibility to and severity of COVID-19.

METHODS

We have analysed common functional polymorphisms within the OAS1 (rs4767027), TMPRSS6 (rs855791), DPP4 (rs3788979), and ZNF335 (rs3848719) genes in SARS-CoV-2 positive subjects (n = 521, different disease severity) and in population controls (n = 2,559 subjects, COVID-19 status unknown).

RESULTS

Neither DPP4 nor ZNF335 were associated with disease susceptibility or severity in the Czech population in any of the models used for calculation. T allele carriers of the OAS1 polymorphism seem to be protective against symptomatic COVID-19 (p = 0.002 calculated for trend; asymptomatic, symptomatic, hospitalised). Similarly, within the TMPRSS6, minor TT homozygotes associated with lower plasma Fe concentrations were underrepresented in the overall patient group (p = 0.044; OR = 0.77, 95% CI: 0.59-0.99), and the difference was mainly driven by the severe COVID-19 subjects. In general, risky homozygotes of these two polymorphisms were less frequent than expected in the group of hospitalised COVID-19 survivors.

CONCLUSIONS

Common variants within OAS1 (rs4767027) and TMPRSS6 (rs855791) play some role in COVID-19 pathology in the Czech Caucasian population. Whether the depletion of minor allele carriers of these two variants is associated with increased COVID-19 mortality, needs to be analysed in an external confirmatory study.

CD14 Polymorphism Is Not Associated with SARS-CoV-2 Infection in Central European Population

A 2021 in silico study highlighted an association between the CD14 polymorphism rs2569190 and increased susceptibility to SARS-CoV-2, which causes coronavirus disease 2019 (COVID-19). The aim of our study was to confirm this finding. We analysed the CD14 polymorphism (C→T; rs2569190) in 516 individuals who tested positive for SARS-CoV-2, with differing disease severity (164 asymptomatic, 245 symptomatic, and 107 hospitalized). We then compared these patients with a sample from the general population consisting of 3,037 individuals using a case-control study design. In comparison with carriers of the C allele, TT homozygotes accounted for 21.7 % of controls and 20.5 % in SARS-CoV-2-positive individuals (P = 0.48; OR; 95 % CI - 0.92; 0.73-1.16). No significant differences in the distribution of genotypes were found when considering co-dominant and recessive genetic models or various between-group comparisons. The CD14 polymorphism is unlikely to be an important predictor of COVID-19 in the Caucasian population in Central Europe.