Loss of smell or taste after contracting Covid associated with genetics- researchers

As scientists are working round the clock to unearth why some people lose their sense of taste and smell after contracting Covid-19, a new study has hinted that there is a genetic factor that increases the odds.

It is still unclear why some people are still unable to smell or have experienced a change in their ability to smell after contracting Covid-19. 

Researchers collected data from a genetic company called 23andme, which conducted an online survey.

The study identified that from more than 1 million participants, of whom 69,841 reported a positive test for the disease, women were 11% more likely than men to report losing those senses after contracting the virus, with 73% of those affected being between 26 and 35 years old.

They however noted that the study had some limitations, including a bias towards those of European ancestry.

Studies suggest that loss of smell, a hallmark symptom of Covid-19, stems from infections taking hold in smell-supporting cells called sustentacular cells.

Janie Shelton, the lead researcher from 23andme, the genes that help people smell reside in the region that is linked to sensory loss during infection.

"It is 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.

And when you lose your taste of smell, often your taste is highly diminished because they go hand in hand.

Taste can also go away without loss of smell.

 Although more research is needed, the study’s findings might help scientists better understand why some people who contract the virus lose one or both senses.

The study was published in Nature genetics on Monday.