The purposes of this study are to identify the gene or genes responsible for an inherited
form of Parkinson's disease and learn more about how the disease develops.
In Parkinson's disease, a deficiency of a brain chemical called dopamine impairs the
function of the part of the brain that controls movement. As a result, patients may have
difficulty moving or they may have uncontrolled movements of their hands and fingers.
Parkinson's disease usually occurs sporadically, with no known cause. In a few families,
however, the disease seems to be inherited through a gene mutation (change). There is a
50-50 chance that a parent with the mutated gene will pass it on to a child. Children who do
inherit the abnormal gene may or may not go on to actually develop Parkinson's disease-the
relative chance of this happening is not known.
Individuals 18 years of age and older from families in which Parkinson's disease appears to
be inherited may be eligible for this study. Participants will have their medical records
reviewed, provide a personal and family medical history (by telephone or in person), and
have a small blood sample (2 tablespoons) taken for genetic studies. The total time required
for the study is about 1 to 2 hours.
Participants are encouraged to meet with a NIH investigator or with a genetics specialist in
their local area before testing to talk about the possible implications for themselves and
their families of the test results....
Mutational analysis in patients with Parkinson's disease and a positive family history will
be undertaken in an effort to identify and better understand the function of defective genes
that cause Parkinson's disease in these individuals. DNA from these individuals is an
important resource for screening candidate genes for mutations, for confirming that genes
identified by other approaches are altered in patients, and for defining the mutational
spectrum in these genes (genotype/phenotype correlation).
Unrelated, anonymous normal individuals will serve as controls for sequence comparisons.
Information about genotypes will not be communicated back to the individuals as part of this
study. While mutational analysis will continue, no further participants will be recruited to
- INCLUSION CRITERIA:
Individuals over the age of 18 from families in which there are three or more individuals
affected with Parkinson's disease (within three generations) and the proband was the only
affected person available or willing to participate in the study
The diagnosis must be supported by accepted clinical criteria: tremor, bradykinesia, and
responsiveness to L-DOPA.
PD may be associated with dementia. The study will lose power if individuals with mental
impairment and PD are excluded. For this reason, decisionally-impaired individuals will be
No one under 18 will be enrolled because, with the exception of the rare autosomal
recessive PD due to parkin mutations, PD does not affect minors. Study design does not
involve testing fetuses.