Fetal costello syndrome with neuromuscular spindles excess and p.Gly12Val HRAS mutation

This case emphasizes the fact that HRAS is the only gene responsible for neuromuscular spindle excess, underlines a correlation between p.Gly12Val mutation and severe CS phenotype and points out the importance of a muscle biopsy performed according to the suitable procedure in neuromuscular disorders for any fetal arthrogryposis.