Parkinsonism and the Human Genome Project

Parkinsonism is a progressive neurological disease process in humans. In its path it decreases dopamine and other cellular chemicals necessary for effective nerve health. Previously, or prior to the latest findings, Parkinsonism was thought to be environmental in origin since no genetic studies pointed to any particular chromosomal involvement. In the studies spoken about here, contrary findings dispute that claim.

In a 2007 study as reported by Current Opinion in Neurology, five genes have been found that relate to Parkinsonism. A new study was done to differentiate the action of the mutated genes between “classical parkinsonism and idiopathic parkinsonism. (Classic Parkinsonism is the usual typical nerve disease where similar causes are reasonably suspected and idiopathic veers off course and none of the usual applications of knowledge fit.)  

In one study, as reported in the August 2007 (Current opinion in Neurology), it was established the “functional role of PINK1 and LRRK2 as kinases.” (Kinases refer to enzymes that cause things to happen, such as, in the above mentioned case, the nerve neurons functioning.) They also learned mutations in ATP13A2 gene points toward a particular type of atypical Parkinsonism.  The study furthered the identification process of genes and their relationship toward more effective treatments. Since, in order to treat, reasonable understanding of what the disease is must be known.   

The National Human Genome Research Institute reports on a study they did in 1997 of a family with links back to familial history of Parkinsonism which definitely shows links to parent to child inheritance tendencies. The nuclear protein coded to was alpha-synuclein. In addition to finding evidence of tau, clumped protein found in the brains of persons with neurological degenerative diseases, they found seven genes that cause some form of Parkinson’s disease.

These studies advanced knowledge about dominant and recessive inheritable diseases. Dominant inheritance is disease potential inherited from parent to child, recessive inheritance is a family with siblings who have the same disease but parents are not afflicted. The gene was present in one of the parents but other more dominant genes kept it down. However, with choices of mate, the recessive gene became prominent and was passed on to the children. Recessive versus dominant genes is a fascinating study of how traits are manifested in offspring.

Genetic testing for Parkinsonism

The PINK1, PARK7, SNCA, LRRK2 and parkin are genes which can now be tested for later development of this disease. Yet, it is not actually recommended except for those who may get the disease before the age of thirty. “PINK1 gene is Autosomal recessive mutations in PINK1 are a rare cause of young-onset Parkinson disease.”

PARK7 gene is Parkinson protein 7 and its normal function is instructional. In other words it directs the action of other genes. Its overall functions aren’t all yet known so far ten mutations have been found that point

Two types of alterations of the SNCA gene cause early-onset parkinsonism.  One change evidenced by a mutated SNCA gene causes the amino acids—protein building blocks—to bunch up or to unfold unnaturally and the other alteration leads to a possible degenerative disease. In the other type of alteration, there’s too much duplication. Excessive copies are made of the SNCA gene. This amounts to an excess of alpha-synuclein.

Learning about Parkinsonism and how Parkinsonism originates, at least in some cases, with gene mutations, is an ongoing study. The extra benefits are enormous. It’s impossible to study one diseased condition without shedding light on another similar disease.