Protein’s genetic defect linked to cardiac arrest

A genetic defect in the protein glycogenin may lead to cardiac arrest, research says, hinting that it can be considered as a diagnosis for heart problems.

A young man’s case triggered the research at Sahlgrenska University Hospital (SUH), University of Gothenburg, Sweden, leading to a brand new diagnosis.

Cardiac arrest occurs when the blood suddenly stops pumping out of the heart. This leads to unconsciousness, and breathing stops on account of an inadequate supply of blood.

An investigation at SUH led to the discovery of not only a new disorder but also how a defect in the protein glycogenin can lead to an energy crisis in the muscle cells.

This protein’s job is to initiate the build-up of glycogen that constitutes the muscle cells’ carbohydrate reserves.

The glycogenin starts the actual process by building up a short chain of around 10 sugar molecules, which can then be turned into glycogen with the help of other enzymes. During strong muscular work the sugar molecules in the glycogen are used to create energy.

“The disorder is characterised by an inability to form the initial chain of sugar molecules,” says Anders Oldfors, who led the research team and is a professor at the Sahlgrenska Academy and SUH consultant.

“This leads to a shortage of glycogen and an energy crisis in the muscle cells that can result in cardiac arrest,” Oldfors adds.

Clinically, the discovery means that this disorder must be considered as a diagnosis when investigating heart problems, an SUH release said.

“But we don’t yet know how common this disorder is,” Oldfors says. “This is something that the future will hold, now that we are in a position to make the correct diagnosis,” he adds.

The findings were published in the New England Journal of Medicine.