SMN1 and spinal muscular atrophy, type 1: Large-scale deletions in chromosome 5q13 that include SMN1, NAIP, SERF1A, and GTF2H2A are observed in patients with type I SMA (Wirth et al., 1995; Burlet et al., 1996; Rodrigues et al., 1996; Velasco et al., 1996; Bürglen et al., 1997; Carter et al., 1997).