African Americans at risk for lead poisoning

A genetic vulnerability that blood tests can miss.

Thester11/Wikimedia Commons

Thester11/Wikimedia Commons

View full image

Children kept arriving at the Detroit clinic with symptoms of lead poisoning. Why didn’t their blood-test results show higher lead levels? Jacquelyn Taylor made a master’s thesis of figuring out what was going on. “There had to be some other underlying biological mechanism,” says Taylor, now an associate professor and associate dean at the School of Nursing.

The answer lay in genetics: 45 percent of the children Taylor tested carried a gene that caused a “pseudo-deficiency” of the enzyme arylsulfatase A. Previous research had shown that a deficiency of that enzyme makes one more susceptible to lead. Taylor found that African American children were three times more likely to have “carrier status for this gene” than children of European descent.

“In thinking now about Flint, Michigan, which is a largely African American community, we’re doing the residents a disservice if we don’t move beyond a one-size-fits-all measure of lead poisoning,” Taylor says. Current screening procedures refer children for treatment only if their lead levels meet the threshold proposed by the Centers for Disease Control.

Publishing last summer in NPG Genomic Medicine—“a call-to-action paper,” as she described it—Taylor and two coauthors outlined a new process that would not only measure lead levels in children’s blood, but also test individual genotypes. Children carrying the gene Taylor found in Detroit would be treated for lead poisoning regardless of their lead levels. 

Starting with a pilot in Flint, Taylor hopes to develop a full-scale genotyping program with support from the National Institutes of Health. Genetic scanning and more treatment will cost money. But, she says, “we can pay for cardiac bypass surgery and mental health services and learning disabilities”—and all the other damage done by lead—or “we can pay to have the genotyping done now.”

The comment period has expired.