Lost smell & taste due to Covid-19? This CCMB study can tell you why

Downregulation is the process by which a cell decreases the quantity of a cellular component, such as RNA or protein, in response to an external stimulus.

Published: 25th September 2021 07:27 AM  |   Last Updated: 25th September 2021 07:27 AM   |  A+A-

nose, smell, covid 19

For representational purposes

Express News Service

HYDERABAD: A new study by the Centre for Cellular and Molecular Biology (CCMB) gives insights into why some people are likely to lose their sense of smell, have more severe symptoms, need follow-ups post recovery, when they are infected with Covid-19. The study involved analysing genes of nearly 36 Covid-19 patients who had varying levels of severity of infection, ranging from ICU care to ward-level care, during the first wave. Five negative Covid-19 samples were also analysed.

The study published in Biorx found that the SARS-CoV-2 tends to react with genes leading to ‘downregulation’ or ‘upregulation’ of some of them, which are responsible for various body functions, like neurological and cardiovascular. Downregulation is the process by which a cell decreases the quantity of a cellular component, such as RNA or protein, in response to an external stimulus. Upregulation, on the other hand, is an increase in these components. Both these processes disrupt the way certain body functions occur.

During the course of the study, upregulation was found in immune response genes, whereas downregulation was seen in genes responsible for neurotransmission, cardiac and muscular contraction.
Researchers, however, said that a majority of the genes were downregulated. “A majority of the genes being downregulated suggests a host shutdown and large-scale systemic effects spanning not just lung and respiratory complications, but also cardiac, endocrine, and neurological issues,” noted the study. This is probably why some people experienced suppression of their sensory receptors, including olfactory and taste receptors.

According to the researchers, such a gene-level of study can show the long-lasting impact Covid has on patients. In the case of myocardial issues, the genes which provide key cardiac proteins and calcium ions crucial for cardiac muscle contraction were also affected.


Disclaimer : We respect your thoughts and views! But we need to be judicious while moderating your comments. All the comments will be moderated by the editorial. Abstain from posting comments that are obscene, defamatory or inflammatory, and do not indulge in personal attacks. Try to avoid outside hyperlinks inside the comment. Help us delete comments that do not follow these guidelines.

The views expressed in comments published on are those of the comment writers alone. They do not represent the views or opinions of or its staff, nor do they represent the views or opinions of The New Indian Express Group, or any entity of, or affiliated with, The New Indian Express Group. reserves the right to take any or all comments down at any time.

flipboard facebook twitter whatsapp