ISLAMABAD, Mar 7: Researchers have uncovered new genetic clues to understanding IgA nephropathy (IgAN), or Berger’s disease, an autoimmune kidney disease and a common cause of kidney failure.
The findings are relevant to IgAN as well as other diseases with similar underlying molecular defects, such as inflammatory bowel disease and certain types of blood disease and cancer.
“Very little is known about the causes of IgAN, genetic or otherwise, so our discovery represents an important step toward developing better therapies for this disease,” said lead author Krzysztof Kiryluk, MD, the Herbert Irving assistant professor of medicine at Columba University Medical Center (CUMC).
The study, conducted by researchers at CUMC and the University of Alabama at Birmingham (UAB) School of Medicine, was published last month in PLOS Genetics.
IgAN occurs when an antibody called immunoglobulin A (IgA) collects in the kidneys, causing inflammation of the glomeruli, the kidneys’ filtering structures. Over time, the inflammation can hinder the kidneys’ ability to filter waste from the blood. About half of patients with IgAN have progressive disease and eventually develop kidney failure. There is no cure for IgAN, but medications, along with blood pressure control, can slow disease progression.
The key molecular defect in people with IgAN is abnormal O-glycosylation of IgA antibodies. O-glycosylation — in which a sugar molecule attaches to an oxygen atom in the amino acid residue of a protein — plays a role in various physiologic processes. Studies of families have shown that problems in the O-glycosylation of IgA are common in people with IgAN and are largely genetic in origin, although the exact genes involved were unknown.