The child cannot rise straight from sitting or lying position like his friends of same age.
A positive Gowers' sign reflects the more severe impairment of the lower extremities muscles; the child with help of upper extremities tries to get up, first by rising to stand on his arms and knees, and then "walking" his hands up his legs to stand upright. This is the tale-tell sign of Duchenne Muscular Dystrophy (DMD)It affects male child, who grows up, to face increasing weakness in the muscles and rarely lives to see his 30th birthday. It is a X-Linked recessive genetic disease, where mother is a carrier.
This is due to defect in production of a protein called dystrophin that is required for muscle health. Nonsense mutations in the dystrophin gene prematurely stop the production of a normal dystrophin protein, leading to a shortened dystrophin protein that does not function properly.
The muscle-specific isoform of the dystrophin gene is composed of 79 exons, and DNA testing and analysis can usually identify the specific type of mutation of the exon or exons that are affected. DNA testing confirms the diagnosis in most cases.
If DNA testing fails to find the mutation, a muscle biopsy test may be performed. A small sample of muscle tissue is extracted (usually with a scalpel instead of a needle) and a dye is applied that reveals the presence of dystrophin. Complete absence of the protein indicates the condition.
The incidence of DMD is approximately 1 in 3,600-6,000 male births per year. In the UK, there are approximately 100 boys diagnosed with DMD each year & at any point of time there are about 1,500 known to have the disease. Approximately 10-15% of patients have a nonsense mutation, which equates to between 150 and 195 pts in the UK [NHSC review].
A new drug, Translarna, also known as ataluren (generic) has been approved that prompts the body to manufacture dystrophin that protects against muscle damage.
A conditional license has been given by European Medicines Agency that allows early access to medicines for life threatening diseases. There are currently no other treatments for the disease.
The newly approved drug is believed to give protein-making parts of cells the ability to "skip over" such genetic defects, so that the cells can resume producing the protein.
