To the Editor,
We agree with Dr. Sadaat [1] that prevalence and mortality of COVID-19 may be attributed to a lot of variables. We have therefore chosen to construct a database of a large single continuous geographical zone to neutralize, as much as possible, a number of confounders. The determination coefficient allows calculating the percentage of the variation that can be explained by the variables included in the model.
It is clear that the majority of the observed variance in COVID-19 prevalence and mortality cannot be explained by the ACE D/I polymorphism alone. This is also the reason why we postulated that the variability in this genotype distribution might partly explain the variable prevalence of the COVID-19. The large differences in population density, testing capacity, the accurate registration of the infection fatality rate, changes in case definition [2], health policy, demographic age distribution, co-morbidities, the variation in the onset of the pandemic, … definitely have contributed to an important variation in the pandemic statistics. So, numerous examples can be given to illustrate this variation. The presence of all these variables makes the observed association between ACE D/I polymorphism and COVID-19 [3] only stronger.
Dr. Sadaat is now going much further in trying to expand the observations in the 33-countries model (with European, North-African and Middle East countries) to other continents by using a linear extrapolation of the equation derived in our study. In particular, some Far East countries (with a very different genetic pattern from the countries included in our database) [4], [5] have been chosen in a very selective way to disprove the correctness of the obtained equation. Taiwan and Japan are islands, which can be geographically well protected against pandemics. South Korea’s only land border is a military demarcation line which does not facilitate international transport. The data of the severely struck Hubei province (high prevalence) have been diluted to the population of mainland China. Similarly, the data of the severely struck Korean Shinchenji Church have been diluted in South Korean statistics. These facts make the comparison with the European/North African/Middle East situation impossible. It is clear that the presented approach based on genetic polymorphisms has limitations: for example, the difference in COVID-19 statistics between North and South Korea is unlikely to be attributed to genetic variability. To evaluate the value of a polymorphism in a multivariate analysis, we have to select a well-defined geographical space, in which the allele frequency varies sufficiently and the classic mortality and contamination risk co-variants vary little. If one selects the whole world and include countries and peoples with large differences in BMI, cardiovascular risk, diabetes prevalence, socio-economic status, organization of health care, public health policy, … every single polymorphism will lose its significance in a multivariate analysis evaluating the influence on infection risk and mortality due to COVID-19.
Research funding: None declared.
Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Competing interests: Authors state no conflict of interest.
References
1. Saadat M. No significant correlation between ACE Ins/Del genetic polymorphism and COVID-19 infection. Clin Chem Lab Med 2020;58:1127–8.10.1515/cclm-2020-0577Search in Google Scholar
2. Tsang TK, Wu P, Lin Y, Lau EH, Leung GM, Cowling BJ. Effect of changing case definitions for COVID-19 on the epidemic curve and transmission parameters in mainland China: a modelling study. Lancet Public Health 2020, doi: https://doi.org/10.1016/S2468-2667(20)30089-X. [Epub ahead of print].10.1016/S2468-2667(20)30089-XSearch in Google Scholar
3. Delanghe JR, Speeckaert MM, De Buyzere ML. COVID-19 infections are also affected by human ACE1 D/I polymorphism. Clin Chem Lab Med 2020;58:1125–6.10.1515/cclm-2020-0425Search in Google Scholar PubMed
4. Reich D. Who we are and how we got here. Oxford: Oxford University Press, 2018, ISBN: 978-0-19-882125-0.Search in Google Scholar
5. Cavalli-Sforza LL, Menozzi P, Piazza A. The history and geography of human genes. Princeton, NJ, USA: Princeton University Press, 1994:1–1088.Search in Google Scholar
©2020 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Editorial
- Critical role of laboratory medicine in the global response to the COVID-19 pandemic
- Reviews
- Hematologic, biochemical and immune biomarker abnormalities associated with severe illness and mortality in coronavirus disease 2019 (COVID-19): a meta-analysis
- COVID-19: progression of disease and intravascular coagulation – present status and future perspectives
- IFCC Recommendations
- Molecular, serological, and biochemical diagnosis and monitoring of COVID-19: IFCC taskforce evaluation of the latest evidence
- Biosafety measures for preventing infection from COVID-19 in clinical laboratories: IFCC Taskforce Recommendations
- Opinion Papers
- The critical role of laboratory medicine during coronavirus disease 2019 (COVID-19) and other viral outbreaks
- Potential preanalytical and analytical vulnerabilities in the laboratory diagnosis of coronavirus disease 2019 (COVID-19)
- Laboratory diagnostics within a modular hospital at the time of Coronavirus disease 2019 (COVID-19) in Wuhan
- Original Articles
- Analytical performances of a chemiluminescence immunoassay for SARS-CoV-2 IgM/IgG and antibody kinetics
- Comparison of throat swabs and sputum specimens for viral nucleic acid detection in 52 cases of novel coronavirus (SARS-Cov-2)-infected pneumonia (COVID-19)
- Routine blood tests as a potential diagnostic tool for COVID-19
- Laboratory predictors of death from coronavirus disease 2019 (COVID-19) in the area of Valcamonica, Italy
- The hemocyte counts as a potential biomarker for predicting disease progression in COVID-19: a retrospective study
- Prominent changes in blood coagulation of patients with SARS-CoV-2 infection
- The value of urine biochemical parameters in the prediction of the severity of coronavirus disease 2019
- Letters to the Editor
- COVID-19 infections are also affected by human ACE1 D/I polymorphism
- No significant correlation between ACE Ins/Del genetic polymorphism and COVID-19 infection
- ACE Ins/Del genetic polymorphism and epidemiological findings in COVID-19
- Laboratory abnormalities in patients with COVID-2019 infection
- Laboratory abnormalities in children with novel coronavirus disease 2019
- Clinical laboratory and SARS-CoV-2 infection: where do we stand?
- Clinical chemistry tests for patients with COVID-19 – important caveats for interpretation
- Antibody tests for COVID-19: drawing attention to the importance of analytical specificity
- Erythrocyte sedimentation rate is associated with severe coronavirus disease 2019 (COVID-19): a pooled analysis
- One disease, different features: COVID-19 laboratory and radiological findings in three Italian patients
- Decreased “WBC*LYM” was observed in SARS-CoV-2-infected patients from a fever clinic in Wuhan
- Assessment of immune response to SARS-CoV-2 with fully automated MAGLUMI 2019-nCoV IgG and IgM chemiluminescence immunoassays
- Coinfection of SARS-CoV-2 and multiple respiratory pathogens in children
- The friendly use of chloroquine in the COVID-19 disease: a warning for the G6PD-deficient males and for the unaware carriers of pathogenic alterations of the G6PD gene
- Potential interference of hydroxychloroquine-glucuronide metabolite on therapeutic drug monitoring of hydroxychloroquine using a mass spectrometry detector
Articles in the same Issue
- Frontmatter
- Editorial
- Critical role of laboratory medicine in the global response to the COVID-19 pandemic
- Reviews
- Hematologic, biochemical and immune biomarker abnormalities associated with severe illness and mortality in coronavirus disease 2019 (COVID-19): a meta-analysis
- COVID-19: progression of disease and intravascular coagulation – present status and future perspectives
- IFCC Recommendations
- Molecular, serological, and biochemical diagnosis and monitoring of COVID-19: IFCC taskforce evaluation of the latest evidence
- Biosafety measures for preventing infection from COVID-19 in clinical laboratories: IFCC Taskforce Recommendations
- Opinion Papers
- The critical role of laboratory medicine during coronavirus disease 2019 (COVID-19) and other viral outbreaks
- Potential preanalytical and analytical vulnerabilities in the laboratory diagnosis of coronavirus disease 2019 (COVID-19)
- Laboratory diagnostics within a modular hospital at the time of Coronavirus disease 2019 (COVID-19) in Wuhan
- Original Articles
- Analytical performances of a chemiluminescence immunoassay for SARS-CoV-2 IgM/IgG and antibody kinetics
- Comparison of throat swabs and sputum specimens for viral nucleic acid detection in 52 cases of novel coronavirus (SARS-Cov-2)-infected pneumonia (COVID-19)
- Routine blood tests as a potential diagnostic tool for COVID-19
- Laboratory predictors of death from coronavirus disease 2019 (COVID-19) in the area of Valcamonica, Italy
- The hemocyte counts as a potential biomarker for predicting disease progression in COVID-19: a retrospective study
- Prominent changes in blood coagulation of patients with SARS-CoV-2 infection
- The value of urine biochemical parameters in the prediction of the severity of coronavirus disease 2019
- Letters to the Editor
- COVID-19 infections are also affected by human ACE1 D/I polymorphism
- No significant correlation between ACE Ins/Del genetic polymorphism and COVID-19 infection
- ACE Ins/Del genetic polymorphism and epidemiological findings in COVID-19
- Laboratory abnormalities in patients with COVID-2019 infection
- Laboratory abnormalities in children with novel coronavirus disease 2019
- Clinical laboratory and SARS-CoV-2 infection: where do we stand?
- Clinical chemistry tests for patients with COVID-19 – important caveats for interpretation
- Antibody tests for COVID-19: drawing attention to the importance of analytical specificity
- Erythrocyte sedimentation rate is associated with severe coronavirus disease 2019 (COVID-19): a pooled analysis
- One disease, different features: COVID-19 laboratory and radiological findings in three Italian patients
- Decreased “WBC*LYM” was observed in SARS-CoV-2-infected patients from a fever clinic in Wuhan
- Assessment of immune response to SARS-CoV-2 with fully automated MAGLUMI 2019-nCoV IgG and IgM chemiluminescence immunoassays
- Coinfection of SARS-CoV-2 and multiple respiratory pathogens in children
- The friendly use of chloroquine in the COVID-19 disease: a warning for the G6PD-deficient males and for the unaware carriers of pathogenic alterations of the G6PD gene
- Potential interference of hydroxychloroquine-glucuronide metabolite on therapeutic drug monitoring of hydroxychloroquine using a mass spectrometry detector