Identifying Clues to Parkinsons Disease
Two new hereditary variants have been identified for Parkinsons disease, say researchers, and also the role genetics play in this neurodegenerative disorder. Although the causes of Parkinsons disease remain unknown, environmental and genetic factors are influences. Genetics play a role in a small percentage of cases which affect people who are under the age of 50. This is known as early-onset Parkinsons. The part genes play in late-onset Parkinsons is not as well known.
In a new study, published in the journal PLoS Genetics, Nicholas Eriksson, PhD, of the California based 23andMe gene testing company which targets direct to consumer testing, says, “About a dozen genetic associations with Parkinsons have been confirmed, and many more remain to be discovered. Each new generic variant we find gets us a little closer to being able to see the full picture of how genes impact this disease. Roughly 10 genetic variants that contribute to Parkinsons had been found and we added another two to the list”. It is estimated that about 25% of the gene variation in susceptibility to developing Parkinsons disease is because of genetic factors according to Eriksson and colleagues. They also estimate that about a quarter of the variation in susceptibility to the disease is due to genetic factors.
SCARB2 has been recognized as one of the newly identified genetic variants with a known Parkinsons disease pathway relating to protein degradation.
The other newly identified variant is called SREBF1, and it is not connected with any known Parkinsons pathway. Do says, “This variant is involved in lipid metabolism. Its association with Parkinsons is not really clear, which is what makes it exciting because it highlights a new area to look at”.
The researchers have estimated that only about 7% of the genetic variants related to Parkinsons disease have been identified highlighting the need for more work to identify the remaining 93%.
Erikssons colleague Chuong B Do, PhD says “While the genetic variants, or mutations, identified to date explain only a small percentage of Parkinsons cases, the gene studies have provided clinically relevant information.” He points out that, “One identified mutation is associated with a 50% lifetime risk for developing the disease. This one variant accounts for a very small percentage of the total disease burden, but for people who do have the variant it is quite significant.” he says.
A genome-wide study was carried out by Chuong B Do, PhD and fellow researchers. Involved in this study were 3,400 Parkinsons patients and almost 30,000 people without the disease who were 23andMe clients. This study took place in an effort to understand genetic influences in both early and late-onset Parkinsons. Recruitment of the Parkinsons patients was aided with the assistance of the Michael J Fox Foundation, the Parkinsons Institute and the National Parkinsons Foundation. The genetic testing company 23andMe funded this study solely.
The completion of the Human Genome Project allowed the study of genome wide association using the following tools: Computerized human genome sequence database, human genetic variation mapping and also the constantly developing technologies which make it easier to analyze the genetic variations related to Parkinsons disease.
Category: Articles