What is a hallmark genetic feature of Duchenne Muscular Dystrophy?

Duchenne Muscular Dystrophy (DMD) is primarily caused by genetic mutations in the dystrophin gene, which is crucial for muscle function. The hallmark feature of DMD is the presence of a frameshift mutation in the dystrophin gene. This type of mutation occurs when nucleotides are added or removed from the gene in a number that is not a multiple of three. As a result, the normal reading frame of the gene is altered, leading to the production of an incomplete or nonfunctional dystrophin protein.

Frameshift mutations often lead to premature stop codons, resulting in a lack of functional dystrophin, which is essential for maintaining muscle cell integrity. The absence of this protein contributes to the muscle degeneration and weakness characteristic of DMD.

While point mutations, deletions, and exon skipping can also impact the dystrophin gene, they are not the hallmark features associated specifically with DMD, which is distinguished by its typical frameshift mutation that results in a loss of dystrophin expression and function. Thus, understanding the nature of the genetic mutation provides insight into the pathophysiology of this condition.