GRHPR

The GRHPR gene provides instructions for making an enzyme called glyoxylate reductase/hydroxypyruvate reductase, which is found primarily in the liver, with smaller amounts in the kidneys. This dual-action enzyme plays a role in preventing the buildup of a potentially harmful substance called glyoxylate by converting it to glycolate. Additionally, this enzyme can convert a compound called hydroxypyruvate to D-glycerate, which is eventually converted to glucose (by other enzymes) and used for energy.

primary hyperoxaluria - caused by mutations in the GRHPR gene

Researchers have identified more than a dozen GRHPR mutations that cause type 2 primary hyperoxaluria. These mutations either introduce signals that disrupt production of the glyoxylate reductase/hydroxypyruvate reductase enzyme or alter its structure. As a result, enzyme activity is absent or dramatically reduced. Glyoxylate builds up because of the enzyme shortage, and it is converted to a compound called oxalate instead of glycolate. Oxalate, in turn, combines with calcium to form calcium oxalate, which the body cannot readily eliminate. Deposits of calcium oxalate can lead to the characteristic features of primary hyperoxaluria, which include kidney stones, kidney damage or failure, and injury to other tissues and organs.