Identification of a novel missense mutation of the SMN ^T gene in two siblings with spinal muscular atrophy

ABSTRACT

Spinal muscular atrophy (SMA) is a motor neuron disease caused by mutations in the telomeric copy of the survival motor neuron ( SMN ^T ) gene. Over 90% of SMA patients harbor a deletion of SMN ^T , 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 SMN ^T . 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.