Regarding diagnostic aids for children with suspected DMD, should all tests including myoenzymes, EMG, muscle biopsy and genetic tests be performed at the same time or should certain tests be performed selectively? After all, electromyography is still painful for the child, and muscle biopsy is even more invasive. If there is a high clinical suspicion of DMD, such as the onset of preschool boys, significant hypertrophy of the gastrocnemius muscle on physical examination, and significant elevation of creatine phosphokinase, it is recommended that instead of electromyography, direct screening for missing or duplicated DMD gene fragments should be performed, and if gene mutations are found, the diagnosis is clear and muscle biopsy is not necessary, and if the gene test results are negative, then muscle biopsy dystrophin immuno Histochemical staining aids in diagnosis. Can a negative DMD gene test rule out Duchenne muscular dystrophy? The answer is no. The DMD gene is large, with 79 exons, and many testing centers in China currently apply different testing methods and detect different exon sites and numbers, with some units only detecting certain hotspot mutations. Even if the MLPA technique is applied to detect 79 exons, it can only detect the deletion or duplication of a large segment of the gene, but not the subtle point mutation, so the positive rate of the genetic test is not 100%, and the negative test result cannot exclude the possibility of Duchenne muscular dystrophy. The diagnosis and treatment of DMD is complicated, parents should consult a professional children’s hospital in order to get authoritative treatment, parents who need to consult me can first apply for a referral appointment to avoid a wasted trip to the hospital when they can’t get a number, you can also communicate with me by phone to see if you need to come to the clinic or local treatment.