Irene Pichler of European Academy of Bozen/Bolzano, an independent research center in Italy and a group of international colleagues, investigated whether there was any evidence of an association between serum iron levels and the risk of Parkinson's disease.
The researchers used a Mendelian randomization approach to investigate this link. The researchers estimated the effect of blood iron levels on the risk of Parkinson´s disease using three polymorphisms -- when two or more clearly different traits exist in the same population of a species -- in two genes, HFE and TMPRSS6.
The researchers performed a meta-analysis combining the results of studies investigating the genetic effect on iron levels, which included almost 22,000 people from Europe and Australia, and a meta-analysis of studies investigating the genetic effect on the risk of Parkinson´s disease, which included a total of 20,809 people with Parkinson's disease and 88,892 controls from Europe and North America.
They then performed three separate Mendelian randomization analyses to estimate the effect of iron on Parkinson disease for the three polymorphisms.
The findings, published in journal PLOS Medicine, suggest increased iron levels in blood are associated with a 3 percent relative reduction in the risk of Parkinson's disease.
The finding is important because it suggests increased blood iron levels might have a protective effect against Parkinson's disease, although the underlying mechanism remains unclear, the study authors said.