HMSN Type VII, also known as hereditary motor and sensory neuropathy type 7, is a rare genetic disorder that affects the peripheral nerves. It is classified as one of the subtypes of hereditary motor and sensory neuropathy (HMSN), which is a group of inherited conditions characterized by damage to the peripheral nerves.
HMSN Type VII specifically involves mutations in the PRPS1 gene. This gene provides instructions for the production of an enzyme called phosphoribosyl pyrophosphate synthetase 1. This enzyme is crucial for the production of nucleotides, which are the building blocks of DNA and RNA.
Mutations in the PRPS1 gene lead to a deficiency or dysfunction of the enzyme, disrupting the normal function of the peripheral nerves. As a result, individuals with HMSN Type VII may experience a wide range of symptoms, including muscle weakness, loss of sensation (particularly in the hands and feet), difficulty with coordination and balance, and muscle wasting. These symptoms typically appear in childhood or adolescence and progressively worsen over time.
Diagnosis of HMSN Type VII is confirmed through genetic testing, which identifies the specific mutations in the PRPS1 gene. Currently, there is no cure for this condition. Treatment mainly focuses on managing the symptoms and preventing complications, such as foot deformities and falls.
Overall, HMSN Type VII is a rare inherited neurological disorder characterized by peripheral nerve damage, motor and sensory impairments, and progressive deterioration of muscle function.
