In Myotonic Dystrophy Type 2, what type of repeat expansion is found in the CNBP gene?

Myotonic Dystrophy Type 2 is characterized by a specific genetic alteration involving the CNBP gene, which is known to contain CCTG repeat expansions. This type of repeat expansion is distinct from other types of repeat disorders seen in similar conditions, such as Myotonic Dystrophy Type 1, which is caused by CTG repeats, and Friedreich's Ataxia, which involves GAA repeats. The presence of CCTG repeats in Myotonic Dystrophy Type 2 leads to the phenotypic manifestations of the disease, including myotonia, muscle weakness, and multisystem involvement. Understanding the specific type of repeat expansion helps in the diagnosis and management of the condition, distinguishing it from other myotonic dystrophies that have different genetic etiologies.