Kidney Disease: It's in the Family

Kidney disease risk in African Americans linked to DNA

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) African Americans have a high risk of kidney failure, especially if they have a family history of the condition. Recent discoveries have now increased the understanding of kidney disease in this high-risk population.

Studying the role of genetics in kidney disease, researchers have revealed better ways to predict the risk of kidney disease for African Americans. The findings could lead to new methods for diagnosis, and eventually new targets for drug treatments.

"Get screened early for kidney disease."

Five recent studies from separate research teams offer new evidence on the link between genetic variants (changes to genes) and the risk of kidney disease in African Americans. According to Eric G. Neilson, M.D., editor-in-chief of the Journal of the American Society of Nephrology, "The five articles published in this issue [of JASN] launch a new era in investigating the underlying risks for developing two very common and complex kidney diseases in African Americans."

For the first study, Ali Gharavi, M.D., from the Columbia University College of Physicians and Surgeons, and colleagues looked at a gene called APOL1 - a gene that has been shown to play a role in kidney disease among African Americans.

Through studying the genes of 74 healthy African Americans and African Americans with different forms of kidney disease, Dr. Gharavi and his fellow researchers found that a variation in the APOL1 gene was linked to a higher risk of two types of kidney disease: focal segmental glomerulosclerosis (FSGS) and HIV-associated nephropathy (HIVAN).

According to Dr. Gharavi, this study confirms the role of the APOL1 gene as a risk factor for kidney disease. He adds that the gene could be used in screening people for their risk of kidney failure.

A second study - which was conducted by Jeffrey Kopp, M.D., from the National Institutes of Health, and colleagues - showed that African Americans with changes in both copies of the APOL1 gene had a much higher risk of developing FSGS and HIVAN.

Dr. Kopp says that his team also found that FSGS tends to develop earlier and to lead to kidney failure more quickly in people with the APOL1 variant, compared to those without the variant.

In a third study, Martin Pollak, M.D., of Beth Israel Deaconess Medical Center, and his team looked at whether the APOL1 gene variants increased the risk for certain types of kidney disease. Nearly 3,000 African Americans participated in their study.

Dr. Pollak and colleagues found that nondiabetic people with two APOL1 gene variants had four times the risk of getting chronic kidney disease, compared to nondiabetic people without the variants. These findings show that the APOL1 variants account for the different rates of kidney disease between African Americans and European Americans, says Dr. Pollak.

In a fourth study, Dr. Pollack, Ravi Thadani, M.D., of Massachusetts General Hospital, and colleagues looked to see if African Americans with the APOL1 gene variant had to start dialysis to treat kidney failure at a younger age than those without the variants.

On average, African Americans with two gene variants started dialysis almost 6 years before those with one variant, and almost 12 years before those with no variants.

Dr. Thadani says that doctors may be able to predict when African Americans with kidney disease will develop kidney failure well before it happens.

The fifth study was conducted by John Sedor, M.D., from Case Western Reserve University and his colleagues. They discovered that the protein made by the APOL1 gene is found in different parts of the kidney in patients with FSGS or HIVAN compared to people without kidney disease.

This protein resides in the walls of small arteries in kidney disease patients. This finding, Dr. Sedor explains, suggests that blood vessels may play a larger role in the course of these two kidney diseases.

All 5 of these studies highlight the degree to which African Americans face the risk of kidney disease. It is crucial to get screened for kidney disease early so that treatment can begin sooner. Early treatment can help protect against kidney failure and death.

These studies are published in the Journal of the American Society of Nephrology

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Review Date: 
October 17, 2011
Last Updated:
October 17, 2011