[1] Virginia Commonwealth Univ, Massey Canc Ctr, Dept Internal Med, Richmond, VA 23298 USA
[2] Virginia Commonwealth Univ, Massey Canc Ctr, Dept Human Genet, Richmond, VA 23298 USA
[3] Louisiana State Univ, Med Ctr, Dept Med, Feist Weiller Canc Ctr, Shreveport, LA 71130 USA
[4] Louisiana State Univ, Med Ctr, Overton Brooks Vet Adm Med Ctr, Shreveport, LA 71130 USA