Professor James J. Cheetham
November 11th, 2013
Parkinson’s Disease: The Shaking Facts
Parkinson’s disease is a progressive disorder of the nervous system that affects your movement1. It was a British physician, named James Parkinson that shown light on the disease in the 1800s2. This disease is a disorder of the brains motor system caused by a loss of dopamine producing brain cells3. It affects approximately one and a half million Americas, plus about 50,000 new patients are diagnosed each year4. Parkinson’s disease has several symptoms, which vary from person to person5. The main symptoms are trembling in the hands, arms, legs, jaw, and face; stiffness of the limbs and trunk; slowed movement; and impaired balance and coordination6. Though the cure for Parkinson’s disease has not been found, there are medications that will improve the symptoms7. Majority of the cases of Parkinson disease happens to the individuals that have no apparent family history of the disorder8. Even though those sporadic cases may not be inherited, there is a possibility that the inheritable pattern is still unknown9. Nevertheless there are familiar cases of the Parkinson’s disease, where depending on what gene is altered we can know the inheritance pattern10. For example the disorder is inherited in an autosomal dominant pattern, if the LRRK2 or SNCA gene is involved11. That means there is a copy of the altered gene in each cell, which is sufficient to cause the disorder12. In many of these situations the person who is affected has one parent with the condition13.
Parkinson’s disease is inherited in an autosomal dominant pattern, if the PARK2, PARK7, or PINK1 gene is involved14. If a gene has an autosomal dominant inheritance pattern, it means that two copies of the gene in each cell are altered15. In most cases it is common for the parents of an individual with autosomal recessive Parkinson disease each to carry one of the altered genes but do not show signs and symptoms of the disorder16. With that said, when genetic alterations modify the risk of developing Parkinson disease, the inheritance pattern is usually unknown17. In spite of Parkinson’s disease being the second most common neurogenetic disorder, the molecular genetic advances have taken off with a set back in comparison with other diseases18. This could be because Parkinson’s disease has long been considered nongentic in essence19. In a large research project for mapping genes in a genetically isolated population of the Southwest in the Netherlands, a large consanguineous pedigree was discovered with four individuals who had an early-onset of Parkinson disease20. A genome-wide scan of this family showed significant evidence for linkage to the chromosome 1p36 region, and this locus was names PARK721. The PARK6 locus was first found in a large Italian family, who originated from Sicily22. After preforming a genome-wide scan, significant information was found for the linkage to the short arm of chromosome 1, in the region 1p35-p36 . The PARK8 locus was identified in a large family from the region of origin in Japan23. A genome-side scan was done in this family, finding significant evidence for linkage of PD to the centromeric region of chromosome 1224. Just identify a disease causing mutation is not enough25. Additional work is needed to make sense of what affect the mutation is having on the normal function of the gene26. It is also feasible for mutations to make the protein hyperactive27. Advancements have been made