A scientific team of Prof. Jan Dumanski, director of the International Research Agenda 3P – Medicine Laboratory in collaboration with researchers from Uppsala University, has published a paper entitled Loss of Y in leukocytes as a risk factor for critical COVID-19 in men in the journal Genome Medicine (IF=15.266). Co-authors of the publication are specianlists for Medicine Laboratory: Natalia Filipowicz, Ph.D., Magdalena Wójcik, Ph.D., Edyta Rychlicka-Buniowska, Ph.D., Marcin Jąkalski, Ph.D., Paweł Olszewski, Monika Horbacz (a Ph.D. student in the Department of Biology and Pharmaceutical Botany), Ulana Juhas, Ph.D. from the Division of Bioenergetics and Physiology of Exercise of the MUG and Karol Wierzba, M.D., from the Department of Rheumatology, Clinical Immunology, Geriatrics and Internal Medicine of the MUG. The main theme of the paper is the relationship between loss of the Y chromosome in white blood cells and increased risk of severe COVID-19 in men.


Men have an increased risk of severe course of COVID-19 compared to women. Researchers at the Medical University of Gdańsk and Uppsala University have now shown that it may be due to the loss of the Y chromosome in part of their white blood cells. The findings could eventually be used to assess the risk of developing severe COVID-19 and perhaps also for improved treatment. A common genetic change in men is loss of the Y chromosome (LOY) in a part of the white blood cells and this change is more common the older you get.


During the COVID-19 pandemic, it became quickly apparent that men were more severely affected by the disease. Up to 75% of patients in intensive care units are men and the proportion of men who died is also higher compared to women. In the current study, the researchers have discovered a connection between LOY and the risk of severe COVID-19.


The researchers studied blood samples taken from over 200 male patients in intensive care units between the beginning of 2020 and the summer of 2021. The analysis showed that LOY was linked both to the severity of the disease, based on the WHO grading and to the risk of dying. Several findings in the study support that LOY is important for the development of severe COVID-19. A higher proportion of LOY could be linked to impaired lung function, e.g. lower oxygenation. Complications in the form of blood clots also showed an association with a higher percentage of LOY in specific types of white blood cells. In addition, it was seen that the higher proportion of cells with LOY was transient. The researchers believe that LOY could be used as a biomarker to predict which patients are at risk of severe disease development from COVID-19.


Our results contribute to a better understanding of the importance that LOY has for the susceptibility to the disease, especially in relation to the function of the immune system. We had the opportunity to analyze samples taken from some of the patients three to six months after they were discharged from the intensive care unit. In these samples, the proportion of cells with LOY had drastically decreased. As far as we know, this is the first time anyone has shown that LOY has dynamic properties linked to an acute infectious disease We also believe that the new knowledge may be relevant to other common viral infections that are more serious for men than women – says Professor Jan Dumański.


The study is a collaboration with researchers at the Uppsala University, Sahlgrenska Academy in Gothenburg, and the National Bioinformatics Infrastructure at Stockholm University.