This post has been updated to indicate that UW's Michael MacDonald was the lead author.
Researchers have homed in on a genetic glitch linked to Mauriac syndrome, which occurs in a subset of children with type 1 diabetes, the Milwaukee Journal-Sentinel reports.
The syndrome affect children whose type 1 diabetes isn't well controlled and is characterized by slowed growth, delayed puberty, and liver enlargement due to glycogen deposition, the team of University of Wisconsin researchers notes in their Diabetes paper.
To search for a genetic cause of the syndrome, the team led by UW's Michael MacDonald sequenced eight genes with roles in glycogen metabolism in a teenager with type 1 diabetes and Mauriac syndrome and his parents. From this, they uncovered a mutation in the PHKG2 subunit of liver glycogen phosphorylase kinase enzyme complex. In addition, they found that this mutant subunit appears to inhibit glycogen phosphorylase kinase enzyme activity and affects glycogenolysis, leading to glycogen accumulation
The mutation wasn't present, the Journal-Sentinel notes, in 250 patients with type 1 diabetes without enlarged livers.