Patient description: The patient is a 16-year-old girl recently diagnosed with myasthenia gravis, class IIa. She complains of diplopia and weakness affecting in her upper extremities. She had a positive anti-AChR antibody test, and her single fiber electromyography (SFEMG) was positive. She is on acetylcholinesterase inhibitor treatment combined with immunosuppressants. But she still has some symptoms. She does not smoke or use illicit drugs. She is not sexually active, and her menses are regular. Her physical exam and lab studies are not remarkable for any other abnormalities. BP: 110/75 Hgb: 11 g/dl WBC: 8000 /mm3 Plt: 300000 /ml Creatinine: 0.5 mg/dl BUN: 10 mg/dl Beta hcg: negative for pregnancy

Clinical trial eligibility criteria: eligible ages (years): 0.0-18.0,  Xlsma DMD X-ALD TSC SMA: patients meet the all the following 1. Clinically manifestation: hypotonia, progressive symmetric and proximal weakness affecting the legs more than the arms, sparing of the facial muscles but often with bulbar muscle weakness. 2. Neurogenic EMG. EMG is also usually not needed in type 1 and 2 children; this investigation can help in more chronic forms in which the phenotype might be less striking. 3. Along with EMG and NCV test, a muscle or nerve biopsy can be used to diagnose spinal muscular atrophy if molecular genetic testing of SMN1 does not identify mutations. 4. Genetic testing of SMN1/SMN2: Homozygous absence of exons 7 and 8 of the SMN1 gene(96%), or only of exon 7, or other mutations. SMN2 copy numbers may vary. Genetic testing is the gold standard of diagnosis  None. - 2. DMD: patients meet the all the following 1. Clinically manifestation: weakness, clumsiness, a Gowers' sign, difficulty with stair climbing, or toe walking. developmental delay or increased concentrations of serum enzymes such as alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, or very high creatine kinase level. 2. Dystrophin gene mutation: dystrophin gene deletion and duplication testing is usually the first confirmatory test best done by MLPA or comparative genomic hybridisation array. Approximately 70% of individuals with DMD have a single-exon or multi-exon deletion or duplication in the dystrophin gene. If deletion or duplication testing is negative, genetic sequencing should be done to screen for the remaining types of mutations that are attributed to DMD (approximately 25-30%). 3. Muscle biopsy: if genetic testing does not confirm a clinical diagnosis of DMD, then a muscle biopsy sample should be tested for the presence of dystrophin protein by immunohistochemistry of tissue cryosections or by western blot of a muscle protein extract. Muscle samples from DMD patient has no dystrophin present, while BMD Becker muscular dystrophy (with some partially functional dystrophin present) None. - 3. X-ALD: patients meet the all the following 1. Clinically manifestation: 1. Attention deficit disorder or hyperactivity; progressive impairment of cognition, behavior, vision, hearing, and motor function follow the initial symptoms and often lead to total disability within six months to two years. 2. Adrenomyeloneuropathy (AMN) manifests as progressive stiffness and weakness of the legs, sphincter disturbances, sexual dysfunction, and often, impaired adrenocortical function; all symptoms are progressive over decades, most commonly in an individual in his twenties or middle age. 3. Magnetic resonance imaging shows cerebral demyelination. 2. Dystrophin gene mutation: The diagnosis of X-ALD is usually established in a female proband with detection of a heterozygous ABCD1 pathogenic variant and elevated VLCFA None. - 4. TSC: criteria:patients meet the all the following A. Clinical diagnostic 1. Major features: (1) Hypomelanotic macules (≥3, at least 5-mm diameter). (2) Angiofibromas (≥3) or fibrous cephalic plaque. (3) Ungual fibromas (≥2). (4) Shagreen patch. (5) Multiple retinal hamartomas. (6) Cortical dysplasias. (7) Subependymal nodules. (8) Subependymal giant cell astrocytoma. (9) Cardiac rhabdomyoma. (10) Lymphangioleiomyomatosis (LAM). (11) Angiomyolipomas (≥2). 2. Minor features: (1)"Confetti" skin lesions. (2) Dental enamel pits (>3). (3) Intraoral fibromas (≥2). (4) Retinal achromic patch. (5) Multiple renal cysts. (6) Nonrenal hamartomas. Two major features or one major feature with ≥2 minor features can diagnose. Either one major feature or ≥2 minor features can diagnosis possibly. B. Genetic diagnostic The identification of either a TSC1 or TSC2 pathogenic mutation in DNA from normal tissue is sufficient to make a definite diagnosis of TSC None. -