Ring fingers may be a sign to having resistance to the coronavirus pandemic, suggests a new study that was published in the Early Human Development journal.
The claim is based on the level of testosterone that a man was exposed to in the uterus, which might be linked to the length of his ring finger. The longer the ring finger is, the greater the exposure that was experienced.
Testosterone is considered to aid in against severe COVID-19-related diseases as it boosts the concentration of angiotensin-converting enzyme 2 (ACE2) within the human body.
Researchers, earlies this month, estimated that men, without citing the ring finger's length, are more than twice as susceptible to death than women are due to the increased amount of ACE2 in their blood.
ACE2 is a receptor and acts as a gatekeeper to cells and attaches itself to the coronavirus and enables it to spread itself into the host.
The increased vulnerability due to ACE2 is counteracted by a reduction in the severity of the symptoms that men may be exposed to. Some studies claim that the increase of ACE2, while allowing for the easier infection of the coronavirus, also protects men from lung damage, as reported by The New York Post.
The study conducted by Swansea University researchers suggests that low testosterone levels in men result in more than twice the death rate due to COVID-19 than those with higher levels of the hormones.
Testosterone level could be one of the significant reasons that result in more men dying from the coronavirus, as believed by doctors.
The Daily Mail reported that experts from Swansea University said men with low testosterone levels are more susceptible to the coronavirus infection.
The severity of the disease
The study took the data of 200,000 people in 41 different countries where the finger lengths of volunteers were already gathered. The index finger and ring finger were measured to the closest millimetre and are denoted as 2D:4D ration.
The study showed that countries with a higher male digit ratio showed low deaths due to the coronavirus and countries with a lower digit ratio suffered lower death rates associated with COVID-19.
Women, on the other hand, did not show any correlation between finger length and coronavirus death rates. The study also revealed similar results with the exclusion of females from the data.
John Manning, the lead researcher of the study, said that the results might give countries where men have longer ring fingers a biological advantage. "Our findings may be men with long ring fingers will experience mild symptoms and could return to work," he added.
The study theorizes that high prenatal testosterone in men, which results in longer ring fingers, lead to higher levels of ACE2 are enough to fight the infection.
While the ACE2 receptors cause the increased chance of infection by the coronavirus, they also limit the infection's spread once it enters the body. The virus causes lung damage by depleting ACE2 receptors.
The increased amount of these receptors, therefore, decreases the likelihood of suffering severe symptoms.
The research concluded that "A strong positive association between male 2D:4D (digit ratio) and mortality may provide a biomarker for male COVID-19 susceptibility and identify those for whom it would be advisable to exercise social distancing."