I am performing research into the causes of an uncommon neurological phenomenon: "trembling chin", that occurs as a benign inherited trait and consists of bouts of trembling of the face muscles at the tip of the chin, often caused by emotional upset. It starts in childhood, right after birth, and seems to decrease with age. The scientific literature from the 1920s contains a report about an extensive family from Oklahoma affected by this harmless condition.
I would be interested to get in touch with descendants from that family.

Adrian Danek, MD PhD
University Department of Neurology
POB 701260
D-81366 Munich
Germany