SNP Shot: Genomic Insights

Pompe disease is a genetic condition resulting from the body's inability to break down glycogen, a complex sugar. This leads to glycogen accumulation within cells, particularly in muscles, which disrupts their normal function.

There are three recognized types of Pompe disease, distinguished by their severity and the age of onset: classic infantile-onset, non-classic infantile-onset, and late-onset.

Classic infantile-onset Pompe disease manifests within the first few months of life. Infants with this type typically present with muscle weakness (myopathy), reduced muscle tone (hypotonia), an enlarged liver (hepatomegaly), and heart problems. They may also struggle with weight gain and growth (failure to thrive) and experience breathing difficulties. Without treatment, this severe form is often fatal due to heart failure within the first year.

Non-classic infantile-onset Pompe disease typically becomes evident around the age of one year. It is marked by delays in motor development, such as rolling and sitting, along with progressive muscle weakness. While the heart might be enlarged (cardiomegaly), heart failure is less common. However, the muscle weakness leads to significant respiratory problems, and most children with this form survive only to early childhood.

Late-onset Pompe disease can appear later in childhood, adolescence, or adulthood. This form is generally less severe than the infantile-onset types and less likely to affect the heart. The primary symptom is progressive muscle weakness, especially in the legs, trunk, and respiratory muscles. As the disease progresses, breathing difficulties can eventually lead to respiratory failure.

Inheritance:

Pompe disease follows an autosomal recessive inheritance pattern. This means that an individual must inherit two copies of the mutated gene (one from each parent) to develop the condition. The parents, who each carry only one copy of the mutated gene, are usually asymptomatic carriers.