Description and physical localization of the bovine survival of motor neuron gene (SMN)

Proximal spinal muscular atrophy (SMA) is an autosomal recessive disease in humans and other mammals, characterized by degeneration of anterior horn c ells of the spinal cord. In humans, the survival of motor neuron gene (SMN) has been recognized as the SMA-determining gene and has been mapped to 5q1 3. In cattle, SMA is a recurrent, inherited disease that plays an important economic role in breeding programs of Brown Swiss stock. Now we have ident ified the full-length cDNA sequence of the bovine SMN gene. Molecular analy sis and characterization of the sequence documents 85 % identity to its hum an counterpart and three evolutionarily conserved domains in different spec ies. Physical mapping data reveals that bovine SMN is localized to chromoso me region 20q12 --> q13, supporting the conserved synteny of this chromosom al region between humans and cattle.