A small number of cases of Parkinson's disease are inherited, researchers have confirmed.
The Mayo Clinic researchers discovered the culpability of a single gene, the alpha-synuclein (SNCA), in about three per cent of people with the disease.
Their work gives further predictions that the gene may prove to be a key player in other incidences, according to the study published in the American Medical Association journal.
"Common variants in the SNCA gene are associated with an increased risk for Parkinson's disease," commented Dr Demetrius Maraganore, the study's lead researcher.
He went on to explain that the causes and development of the disease remains more complex than the presence of a single gene.
"We know that Parkinson's disease is a complex disease. It isn't caused by any single factor. It's caused by multiple factors. Those factors may be genetic or environmental," he said.
"But we know, with confidence, that alpha-synuclein gene variation is one of the puzzle pieces that belongs to the big picture of Parkinson's disease," he concluded.
Although it is possible that the SNCA gene could be a new focus for treatment, experts emphasised that this potential was already known.
The Parkinson's Disease Foundation stated that Parkinson's remains a disease with no cure.