In the latter case, the authors proposed that homozygous truncating mutations result in a severe form of HSAN6, with congenital defects and early lethality, while heterozygosity for a truncating or missense mutation maintains enough dystosin expression and function to allow a normal lifespan, albeit with symptoms of HSAN6.DST is involved in maintaining cytoskeleton integrity and intracellular transport systems, each of which are critical to the normal function of the particularly long neurons found in the peripheral nervous system. Its believed that this disrupts the cells internal autophagy process, in which toxic proteins and other normally-occurring debris are captured and transported to the cell center for recycling or destruction. In neurons, autophagosomes, are generated at the ends of the neuron to carry the discardable material, and they are then transported toward center. With the intracellular transport system disrupted by a mutation in DST, the autophagosomes are unable to carry away the debris, which builds up at the ends of the neuron, leading to damage. Type 7
Type 8
Genetics
Associated genes
Diagnosis
Treatment
References
https://www.jsaapd.com/abstractArticleContentBrowse/JSAAPD/1/4/3/26394/abstractArticle/Article

Further reading
GeneReviews/NIH/NCBI/UW entry on Hereditary Sensory and Autonomic Neuropathy IV
GeneReviews/NIH/NCBI/UW entry on Hereditary Sensory Neuropathy Type I
GeneReviews/NIH/NCBI/UW entry on Hereditary Sensory and Autonomic Neuropathy Type II


== External links ==
Ewing sarcoma is a type of cancer that forms in bone or soft tissue. Symptoms may include swelling and pain at the site of the tumor, fever, and a bone fracture. The most common areas where it begins are the legs, pelvis, and chest wall. In about 25% of cases, the cancer has already spread to other parts of the body at the time of diagnosis. Complications may include a pleural effusion or paraplegia.It is a type of small round cell sarcoma. The cause of Ewing sarcoma is unknown. Most cases appear to occur randomly. Sometimes there has been a germline mutation. The underlying mechanism often involves a genetic change known as a reciprocal translocation. Diagnosis is based on biopsy of the tumor.Treatment often includes chemotherapy, radiation therapy, surgery, and stem cell transplant. Targeted therapy and immunotherapy are being studied. Five-year survival is about 70%. A number of factors, however, affect this estimate.James Ewing in 1920 established that the tumor is a distinct type of cancer. It affects about one in a million people per year in the United States. Ewing sarcoma occurs most often in teenagers and young adults and represents 2% of childhood cancers. Caucasians are affected more often than African Americans or Asians. Males are affected more often than females. Signs and symptoms
Ewing sarcoma is more common in males (1.6 male:1 female) and usually presents in childhood or early adulthood, with a peak between 10 and 20 years of age.