Laboratoire de Génétique biochemique et Laboratoire de recherches sur les protéines, I.N.R.A., Jouy-en-Josas, France
The A variant of bovine alpha(s1) casein is devoid of the segment of 13 amino acid residues which occupies the 14th to 26th position from the NH(2)-terminal in the polypeptide chain (198 residues) of the B and C variants.