[1] Univ Minnesota, Dept Genet Cell Biol & Dev, Minneapolis, MN 55455 USA
[2] Univ Minnesota, Dept Neurosurg, Minneapolis, MN 55455 USA
[3] Medtronic Inc, Biosci LT220, Minneapolis, MN 55432 USA
[4] Univ Minnesota, Inst Human Genet, Gene Therapy Program, Minneapolis, MN 55455 USA