[1] Vanderbilt Univ, Med Ctr, Ctr Human Genet Res, Nashville, TN 37232 USA
[2] Vanderbilt Univ, Med Ctr, Dept Physiol & Mol Biophys, Nashville, TN 37232 USA
[3] VA Hosp Med Ctr, Dept Psychiat, Nashville, TN USA
[4] Duke Univ, Dept Neurol, Durham, NC USA
[5] Duke Univ, Ctr Human Genet, Durham, NC USA
[6] Duke Univ, Dept Med, Durham, NC USA