Researchers study whether common genetic trait may raise risk of coronavirus complications in Black Americans

The coronavirus pandemic has highlighted a stark racial disparity: Black Americans who contract the coronavirus are dying at twice the rate of whites.

Dr. Jason Payne and researchers at Morehouse School of Medicine in Atlanta are studying whether a genetic trait millions of Americans carry could raise their risk of suffering complications from the virus.

"We know that COVID 19 has disproportionately affected African Americans and communities of color," Dr. Payne says.  So, what we are trying to understand is if there is a potential biological basis for this."

29-year-old Kendrick Merrells of Powder Springs, Georgia, has spent the last 7 months trying to steer clear of the coronavirus.

"I do not come into contact with anyone I don't have to, or go anywhere I don't have to," Merrell says.

Merrells needs to be extra careful, because he is one of about 100,000 Americans, mostly people of color, who have sickle cell disease.

The hereditary blood disorder causes normally round red blood cells to become sickle shaped, clogging blood vessels, damaging organs and triggering severe pain episodes. 

Dr. Payne, a sickle cell specialist at Morehouse School of Medicine says severe a lung complication known as acute chest syndrome is also common with this disease.

Merrells says he has been hospitalized twice since the pandemic began, both times developing acute chest syndrome.

"Anytime I'm hospitalized, I wonder if this is the last time I'll be here," he says.

Dr. Payne says respiratory infections like pneumonia can hit sickle cell patients especially hard.

"So, with COVID-19 being a respiratory illness, we're seeing that trajectory, seeing that patients with sickle cell and COVID-19 are getting very sick with this," Payne says.

People with sickle cell disease may not be the only ones at risk of complications. 

Nearly 3 million Americans, or about 1 out of every 12 African Americans, are sickle cell trait carriers, meaning they have inherited one of two sets of the sickle cell genes but not the disease itself.

Cardiologist Dr. Herman Taylor, Director of the Cardiovascular Research Institute at Morehouse School of Medicine, is part of a study with Dr. Payne at Grady Memorial Hospital to find out whether sickle cell trait carriers may also be at increased risk of becoming very ill, should they contract the virus.

"Sickle trait is a silent condition in the vast majority of cases," Dr. Taylor says.  "Under extreme circumstances, sickle trait will manifest.  Things that produce very low oxygen levels can trigger sickle trait from going from a silent condition to a very active condition."

One of those triggers is a severe drop in oxygen, which can be a life-threatening complication in some people with the coronavirus.

"COVID has a lot of characteristics that are common to sickle cell episodes,

like inflammation, like blocked arteries and pain," Dr. Taylor says.  "Those things are could potentially, could theoretically, at least, be aggravated by the combination of COVID and sickle trait. So, we're not suggesting this is the reason that African Americans are having a more difficult time with COVID.    We're suggesting this may play a role that up to his point we're not sure of.  We don't know."