<unk>  is an autosomal dominant myopathy with considerable variation in penetrance, leading to a spectrum of familial phenotypes (only one parent needs to carry the gene mutation to affect the children, but not all family members who share the gene are affected to the same degree). Specific diseases include: * Hypokalemic<unk>  (), where potassium leaks into the muscle cells from the bloodstream. * Hyperkalemic<unk>  (), where potassium leaks out of the cells into the bloodstream. * Paramyotonia congenita (), a form which often accompanies hyperkalemic<unk> , but may present alone. The primary symptom of paramyotonia congenita is muscle contracture which develops during exercise or activity. Paramyotonia congenita attacks may also be triggered by a low level of potassium in the bloodstream. This means people with both hyperkalemic<unk>  and paramyotonia congenita can have attacks with fluctuations of potassium up or down. * Andersen-Tawil syndrome (), a form of<unk>  that includes significant heart rhythm problems, fainting and risk of sudden death. Potassium levels may be low, high, or normal during attacks of ATS. Patients with ATS may also have skeletal abnormalities like scoliosis (curvature of the spine), webbing between the second and third toes or fingers (syndactyly), crooked fingers (clinodactyly), a small jaw (micrognathia) and low-set ears. Patients need to have another form of<unk>  to have the Andersen-Tawil. If a patient has hypo or hyper<unk>  they have a 50% chance of getting Andersen-Tawil. They just have to have the gene that causes it. This is a rare occurrence of having this. Only around 100 people in the world are recorded to have it.
Periodic paralysis
Myotonia congenita
Paramyotonia congenita
Klumpke paralysis
Paroniria
Holmes tremor
Ataxic cerebral palsy
Episodic ataxia