What is the primary characteristic that distinguishes Becker muscular dystrophy from Duchenne?

Becker muscular dystrophy is primarily distinguished from Duchenne muscular dystrophy by the age of onset. In Becker muscular dystrophy, symptoms generally appear later in childhood or adolescence, while Duchenne muscular dystrophy typically presents earlier, often between ages 2 to 5. This difference in age of onset is a key factor in diagnosis and can affect the progression of the disease and the overall prognosis for affected individuals.

While Becker muscular dystrophy tends to have a milder course and slower progression compared to Duchenne muscular dystrophy, the timing of symptom development is a more defining characteristic that marks the differentiation of the two disorders. Understanding this aspect aids in early diagnosis and can help shape management strategies.