sh-Polypeptide-156 is a single chain recombinant human peptide, produced by fermentation in E. coli. The starting gene which is a synthesized copy of the human gene that codes for Growth/Differentiation Factor 8, is used as such or adapted to the production host. It contains a maximum of 371 amino acids which may contain disulfide bonds and/or glycosylation. The protein consists of the proper sequence of the 20 standard amino acids.