In order to investigate the spinal muscular atrophy (SMA) disease processes, the expression
of the survival motor neuron gene (SMN) has been analyzed in human fetal tissues using RT–
PCR andin situhybridization. These studies allowed the detection of SMN RNA in all the
examined tissues, with no significant variation between different developmental stages. In
particular, SMN mRNA was detected in spinal cord (dorsal and ventral portions), skeletal
muscle, lung, heart, kidney, liver, and spleen. Moreover, RT–PCR studies demonstrated that …