January 31, 2017
A new study has found an Amerindian-specific genetic variant that influences a kidney trait in Hispanics/Latinos, thereby confirming shared genetic risk for kidney disease among Hispanics/Latinos and American Indians.
The paper, led by Nora Franceschini, MD, MPH, research associate professor of epidemiology at the UNC Gillings School of Global Public Health, and Jianwen Cai, PhD, Cary C. Boshamer Distinguished Professor and interim chair of biostatistics at the Gillings School, was published online Jan. 30 in the Journal of the American Society of Nephrology (JASN).
The study extends earlier work by the authors, published Sept. 20, 2016, in JASN. That research reported certain African-ancestry variants confer risk of chronic kidney disease in Hispanics/Latinos.
In the current work, Franceschini and colleagues evaluated a mixture of European, African and Amerindian (Native Americans in U.S. and Canada) ancestries in Hispanics/Latinos to find genomic regions associated with albumin excretion in urine. A protein that helps build muscle, repair tissue and fight infection, albumin typically is found in blood. If kidneys are not filtering one’s blood effectively, albumin may ‘leak’ from the kidneys into urine. This marker for kidney disease is called “albuminuria.”
The researchers identified an Amerindian region associated significantly with urine albumin excretion, which was driven by a variant present only in American Indians and is located in a regulatory region of the BCL2L11 gene, which is programmed for a process of cell self-destruction.
The association of the variant with urine albumin excretion was validated in an independent study of Pima Indians.
“This study shows the importance of studying diverse ethnic populations in genetic studies,” Franceschini said. “It provides exciting new evidence for shared genetic risk for kidney disease among Hispanics/Latinos and American Indians, and supports the need for additional studies focused on these populations to better understand the overall risk of kidney disease in the U.S. population.”
Other co-authors are from the University of Washington at Seattle School of Public Health; National Institute of Diabetes and Digestive and Kidney Diseases, in Phoenix; Loyola University; National Heart, Lung and Blood Institute, in Bethesda; University of Miami (Fla.); Brigham and Women’s Hospital, Beth Israel Deaconess Medical Center and Harvard Medical School; and the University of Illinois at Chicago.
The study, “Admixture Mapping Identifies an Amerindian Ancestry Locus Associated with Albuminuria in Hispanics in the United States,” is available online.