heredity question

[Rosemary & Rollin Dexter <rdxtr@xxxxxxxx>]

We just got back from visiting my husband's brother and it appears he also
has Parkinson's.  He hasn't been officially diagnosed but he has many
symptoms; tremor of his left hand and of his lower jaw, voice problems,
stooped posture, no energy.  We have encouraged him to see his wife's
doctor as soon as possible (she does have Parkinson's) hoping that
medications will help him to feel better.
My husband had two aunts, one had Parkinson and we think the other did too.
 She lived in New Zealand and the family doesn't want to discuss it.
However, the last pictures we had of her showed a very "masked" face and we
know she had some kind of mental and movement problems.  My question is,
with so many in the family having Parkinson's is there any test yet for
detecting it early.  Our son has a slight tremor in his hand and so does
the daughter of my brother-in-law.  And the next question is, is early
detection  helpful in any way?

Nancy Shalaes asked if there was interest in finding out more of a study on
this subject and I surely would.  Thanks to anyone who can shed some light
on the subject.

Rosemary Dexter, cg for Dex 75/5 rdxtr@xxxxxxxx