Identification of a novel missense mutation of the SMNT gene in two siblings with spinal muscular atrophy

Spinal muscular atrophy (SMA) is a motor neuron disease caused by mutations in the telomeric copy of the survival motor neuron (SMNT) gene. Over 90% of SMA patients harbor a deletion of SMNT, but relatively few base-pair mutations have been reported. We report here a novel G279C mutation with a G to T transversion on exon 7 (nucleotide position 868) of SMNT. Another missense mutation has been reported recently on position 869. The fact that two mutations on the same codon both result in SMA suggest a functional significance of this amino acid within the SMN protein. © Springer-Verlag 1998.