[1] COLUMBIA UNIV,HOWARD HUGHES MED INST,722 W 168TH ST,NEW YORK,NY 10032
[2] COLUMBIA UNIV,DEPT BIOCHEM & MOLEC BIOPHYS,NEW YORK,NY 10032
[3] UNIV PENN,DEPT HUMAN GENET,PHILADELPHIA,PA 19104
[4] CTR DIS CONTROL,ATLANTA,GA 30333
[5] SK&F LABS,KING OF PRUSSIA,PA 19406