What is Pathognomic

The nervous system (NS) is comprised of nerve cells (neurons), which transfer and process information, and neuroglia (or glial cells), which provide the supportive framework neurons need to function effectively. There are two divisions of the nervous system: central (CNS) and peripheral (PNS). The CNS consists of the brain and spinal cord and forms an intricate network of specialised cells that are responsible for coordinating all bodily functions. The PNS delivers sensory information from peripheral sensory tissues and systems to the CNS and carries motor commands from the CNS to peripheral tissues. This chapter discusses 15 diseases that directly affect the nervous system mostly caused by mutations in a single gene, with others having more complex modes of inheritance. They include Alzheimer's Disease, epilepsy, essential tremor, familial Mediterranean fever, Friedreich's ataxia, Huntington's disease, maple syrup syndrome, Menkes disease, narcolepsy, Parkinson's Disease, phenylketonuria, Refsum disease, spinal muscular atrophy, tangier disease, and spinocerebellar ataxia.