* Not a rare disease
Other Names for this Disease
- Paralysis agitans
- Parkinson's disease
- Primary parkinsonism
- Shaking palsy
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 Parkinson disease affects about 1 to 2 percent of people over the age of 60 years and the chance of developing Parkinson disease increases as we age. Although some Parkinson disease cases appear to be hereditary most cases are sporadic and occur in people with no apparent history of the disorder in their family. When three or more people are affected in a family, especially if they are diagnosed at an early age (under 50 years) there may be a gene making this family more likely to develop the condition. Currently, seven genes that cause some form of Parkinson's disease have been identified. Mutations (changes) in three known genes called SNCA (PARK1),UCHL1 (PARK 5), and LRRK2 (PARK8) and another mapped gene (PARK3) have been reported in families with dominant inheritance. Mutations in three known genes, PARK2 (PARK2), PARK7 (PARK7), and PINK1 (PARK6) have been found in affected individuals who had siblings with the condition but whose parents did not have Parkinson's disease (recessive inheritance). There is some research to suggest that these genes are also involved in early-onset Parkinson's disease (diagnosed before the age of 30) or in dominantly inherited Parkinson's disease but it is too early yet to be certain. However, in most cases inheriting a mutation will not cause someone to develop Parkinson's disease because there may be additional genes and environmental factors determining who will get the condition, when they get it and how it affects them.Parkinson disease belongs to a group of conditions called movement disorders. The four main symptoms are tremor, or trembling in hands, arms, legs, jaw, or head; rigidity, or stiffness of the limbs and trunk; bradykinesia, or slowness of movement; and postural instability, or impaired balance. These symptoms usually begin gradually and worsen with time. As they become more pronounced, patients may have difficulty walking, talking, or completing other simple tasks. Not everyone with one or more of these symptoms has Parkinson disease, as the symptoms sometimes appear in other diseases as well.
Last updated: 11/5/2015
- Parkinson's Disease: Hope Through Research. National Institute of Neurological Disorders and Stroke. September 30, 2011; http://www.ninds.nih.gov/disorders/parkinsons_disease/detail_parkinsons_disease.htm#127443159. Accessed 10/2/2011.
- Learning about Parkinson Disease. National Human Genome Research Institute. March 14, 2014; http://www.genome.gov/10001217. Accessed 11/5/2015.
- The Genetic Alliance is an international coalition comprised of more than 600 advocacy, research and health care organizations representing millions of individuals with genetic conditions. Click on the link to view information on this topic.
- Genetics Home Reference (GHR) contains information on Parkinson disease. This website is maintained by the National Library of Medicine.
- MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
- The Merck Manuals Online Medical Library provides information on this condition for patients and caregivers.
- The National Human Genome Research Institute's (NHGRI) mission encompasses a broad range of studies aimed at understanding the structure and function of the human genome and its role in health and disease. Click on the link to view the information page on this topic.
- The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
- The National Organization for Rare Disorders (NORD) is a federation of more than 130 nonprofit voluntary health organizations serving people with rare disorders. Click on the link to view information on this topic.
- Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
- MeSH® (Medical Subject Headings) is a terminology tool used by the National Library of Medicine. Click on the link to view information on this topic.
- Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
- PubMed is a searchable database of medical literature and lists journal articles that discuss Parkinson disease. Click on the link to view a sample search on this topic.