spinal muscular atrophy, sma, a genetic neuromuscular disorder with progressive muscle wasting

spinal muscular atrophy sma disorder code carcinogen genes spiral medicine technology helix 3d genetic genome biochemistry science damage concept biotechnology medical research dna molecular biology gene chromosome evolution structure mutation clone illustration microscopic molecule disease type 0 1 2 3 4 werdnighoffmann dubowitz kugelbergwelander juvenile form adult onset infant areflexia neuromuscular smn