Researchers from 23andMe, a genomics and biotechnology company, analyzed data from 69,841 individuals in United States of America And United Kingdom Those who took the online survey after testing positive for COVID-19 compared those who reported a loss of sense of taste or smell with those who did not.
Among those who tested positive for COVID-19, 68% of participants reported a loss of taste or smell, women interviewed were 11% more likely than men to report symptoms, and about 73% were between 26 and 35 years old. study.
The study also found that loss of taste or smell was more common among those who had tested for COVID-19 compared to those who tested negative but reported flu-like symptoms, noting that those of East Asian or African American ancestry were less likely. to report reports. Loss of sense of smell or taste compared to humans Europe Ancestor.
The research team compared the genetic differences of those who reported loss of taste or smell with those who did not, and found a site near two genes, UGT2A1 and UGT2A2, associated with the sense of smell associated with loss of smell. Taste and smell after being infected with COVID-19.
Even though the past Animals Studies have shown that this gene, which is expressed in our nasal tissues, is involved in the deletion of ‘odor’ and previous experimental studies have shown that loss of smell is linked to tissue damage along the lining of the nose, and the authors acknowledge that it is unclear how the gene is actually involved, simply because “… may play a role in the physiology of the affected cells and the resulting functional impairment that contributes to the loss of the ability to function.” building. “
Although this was a large-scale study, it had several limitations, including bias towards participants of European descent, and relying solely on self-report surveys without a clinical evaluation of participants.And and the inability to ‘separate’ the loss of taste from smell because they were both included in one survey question.
It should be noted that [gene] The variant identified in this study also appears to be associated with a general ability to smell, which may indicate that those with a high sensitivity to smell or taste may be more likely to notice this loss of sense as a result of SARS-CoV-2 infection,” the authors wrote. He said.
Previous research has shown that loss of taste and smell is linked to “failure to protect the sensory cells of the nose and tongue from viral infection,” said Daniel Reed, associate director of the Monell Chemical Senses Center in Philadelphia. Reed is studying person-to-person differences in loss of taste and smell due to COVID-19, but is not yet part of study.
“This study points in a different direction,” he said. “The pathways that break down the chemicals that cause taste and smell in the first place may be overactive or inactive, reducing or distorting taste and smell abilities.