News

A genetic analysis hints at why COVID-19 can mess with smell

People with variants near smell-related genes may have a higher risk of losing smell or taste.
Erin Garcia de Jesús, Science News
By Erin Garcia de Jesús, Science News
Jan. 23, 2022

For many people, one of the fastest tip-offs that they have COVID-19 is the loss of taste or smell. Now researchers have pinpointed some genetic variants in people that may make it more likely that the coronavirus might rob them of these senses.

A study of nearly 70,000 adults with COVID-19 found that individuals with certain genetic tweaks on chromosome 4 were 11% more likely to lose the ability to smell or taste than people without the changes, researchers report January 17 in Nature Genetics. The data come from people who’d had their DNA analyzed by genetic testing company 23andMe and self-reported a case of COVID-19.

Two genes, UGT2A1 and UGT2A2, that help people smell reside in the region of chromosome 4 linked to sensory loss during infection, epidemiologist Janie Shelton of 23andMe and colleagues found. Both genes make enzymes that metabolize substances called odorants, which produce distinctive smells.

Studies suggest that loss of smell, a hallmark symptom of COVID-19, stems from infections taking hold in smell-supporting cells called sustentacular cells. It’s possible that the genetic variants near UGT2A1 and UGT2A2 could affect how the two genes are turned on or off to somehow mess with smell during an infection, Shelton says.

The team combined loss of smell and taste in one survey question so the study can’t parse whether the genetic variants are involved in the loss of one sense over the other. “When you lose your taste of smell, often your taste is highly diminished,” Shelton says. Taste can also go away without loss of smell.

Some people have a sustained loss of smell, even after the coronavirus leaves their bodies, Shelton says. Understanding how the virus snuffs out sniffing ability could help researchers find ways to bring it back.

This story was originally published by Science News, a nonprofit independent news organization.

Enjoy reading ASBMB Today?

Become a member to receive the print edition monthly and the digital edition weekly.

Learn more
Erin Garcia de Jesús, Science News
Erin Garcia de Jesús, Science News

Erin I. Garcia de Jesus is a staff writer at Science News. She holds a Ph.D. in microbiology from the University of Washington and a master’s in science communication from the University of California, Santa Cruz.

Get the latest from ASBMB Today

Enter your email address, and we’ll send you a weekly email with recent articles, interviews and more.

Latest in Science

Science highlights or most popular articles

Evolutionary constraints on disordered proteins
Feature

Evolutionary constraints on disordered proteins

Dec. 5, 2022

Best of BMB 2022: “There’s evidence that there must be conservation of function — so how does this happen, if the sequence changes so much?”

COVID-19, preprints and journalists
Science Communication

COVID-19, preprints and journalists

Dec. 3, 2022

Researchers find that news stories often fail to mention when studies haven’t been peer reviewed.

From the journals: MCP
Journal News

From the journals: MCP

Dec. 2, 2022

Muscling in on a signaling pathway. Probing weaknesses in the T cell surface. Improving single-cell proteomics two ways. Read about papers on these topics recently published in the journal Molecular & Cellular Proteomics.

Unconventional phosphoinositide synthesis
Lipid News

Unconventional phosphoinositide synthesis

Nov. 29, 2022

Researchers uncover a clue to how disease-causing bacteria synthesize the tiny lipids known as 3-phosphoinositides to hijack host cells.

From the journals: JLR
Journal News

From the journals: JLR

Nov. 25, 2022

A new way to measure lipoprotein(a). A new source of metabolized cholesterol. A new way to count ceramides. Read about articles on these topics recently published in the Journal of Lipid Research.

How proteolysis controls the Legionnaires’ pathogen
Journal News

How proteolysis controls the Legionnaires’ pathogen

Nov. 24, 2022

The bacterium that causes this severe pneumonia has a biphasic life cycle that depends on regulation of protein homeostasis.