MCT8-specific thyroid hormone cell transporter deficiency (THCT deficiency) is an inherited disorder that is characterized by severe mental retardation, an impaired ability to speak, diminished muscle tone (hypotonia), and/or movement abnormalities. With the exception of poor muscle tone, most affected infants appear to develop normally during the first months of life. However, by about two months of age, affected infants may seem  Read More

MCT8-specific thyroid hormone cell transporter deficiency (THCT deficiency) is an inherited disorder that is characterized by severe mental retardation, an impaired ability to speak, diminished muscle tone (hypotonia), and/or movement abnormalities. With the exception of poor muscle tone, most affected infants appear to develop normally during the first months of life. However, by about two months of age, affected infants may seem  Read More

Dejerine-Sottas disease is an inherited neurological disorder that progressively affects mobility. Peripheral nerves become enlarged or thickened leading to muscle weakness. Progress of the disorder is irregular and often accompanied by pain, weakness, numbness, and a tingling, prickling or burning sensation in the legs. Many people with Dejerine-Sottas disease continue to lead active lives. Most neurologists now consider this diso  Read More

MERRF (Myoclonus Epilepsy with Ragged-Red Fibers) syndrome is an extremely rare disorder that begins in childhood and affects the nervous system and skeletal muscle as well as other body systems. The distinguishing feature in MERRF is myoclonus, consisting of sudden, brief, jerking spasms that can affect the arms and legs or the entire body. In addition, individuals with MERRF syndrome may have muscle weakness (myopathy), an impaired ability t  Read More

Fukuyama type congenital muscular dystrophy (FCMD) is one of several forms of a rare type of muscular dystrophy known as congenital muscular dystrophy. It is inherited as an autosomal recessive trait. Symptoms of this disorder are apparent at birth and progress slowly. In addition to general muscle weakness and deformities of the joints (contractures), FCMD is often accompanied by seizures, mental retardation and speech problems. This disorder  Read More

Giant axonal neuropathy is a rare neuropathy that severely affects the peripheral as well as the central nervous system. The first symptoms appear in early childhood. This disorder is characterized by abnormalities in the peripheral and central nervous systems including low muscle tone (hypotonia), muscle weakness, decreased reflexes, impaired muscle coordination (ataxia), seizures and intellectual disability. Pale, tightly curled hair is freq  Read More

Hereditary sensory and autonomic neuropathy type II (HSAN2) is a rare genetic disorder that usually begins in childhood by affecting the nerves that serve the lower legs and feet and the lower arms and hands. Symptoms start with inflamed fingers or toes, especially around the nails. Numbness and tingling sensations in the hands and feet may also occur. Eventually, affected individuals lose feeling (sensation) in the hands and feet. This sensor  Read More

Juberg-Marsidi syndrome is an extremely rare X-linked genetic disorder that is fully expressed in males only, and is apparent at birth (congenital) or during the first few weeks of life (neonatal period). Affected children exhibit severe mental retardation; delays in reaching developmental milestones (e.g., crawling, walking, etc.); muscle weakness; diminished muscle tone (hypotonia); and/or delayed bone growth as well as growth retardation, r  Read More

Lambert-Eaton myasthenic syndrome (LEMS) is a rare autoimmune disorder characterized by the gradual onset of muscle weakness, especially of the pelvic and thigh muscles. Approximately 60 percent of LEMS cases are associated with a small cell lung cancer (SCLC), and the onset of LEMS symptoms often precedes the detection of the cancer. The LEMS patients with cancer tend to be older and nearly always have a long history of smoking. In cases in w  Read More

Marinesco-Sjogren syndrome (MSS) is a rare genetic disorder that affects multiple organ systems of the body. Common symptoms include difficulty coordinating voluntary movements due to degeneration (atrophy) of the cerebellum (cerebellar ataxia), clouding of the lenses of the eyes (cataracts), delays in the acquisition of skills requiring the coordination of muscular and mental activity (psychomotor development), diminished muscle tone (hypoton  Read More

Camurati-Engelmann disease is a rare genetic disorder characterized by progressive widening and malformation of the shafts of the long bones (diaphyseal dysplasia). Major symptoms may include bone pain, particularly in the legs; skeletal abnormalities; and/or weakness and underdevelopment (hypoplasia) of various muscles. Pain and weakness of the leg muscles may result in an unusual "waddling" walk (gait). Camurati-Engelmann disease is inherite  Read More

POEMS syndrome is an extremely rare multisystem disorder. POEMS is an acronym that stands for (P)olyneuropathy, disease affecting many nerves; (O)rganomegaly, abnormal enlargement of an organ; (E)ndocrinopathy, disease affecting certain hormone-producing glands that help to regulate sexual function, and certain metabolic functions; (M)onoclonal gammopathy or M proteins; and (S)kin abnormalities. Common symptoms include progressive weakness of  Read More