", Y is an amino acid from the group consisting of Thr, Ala and Ser, Z is an amino acid from the group consisting of Asn, Gln, Asp, Glu, Gly, Ser, Thr, Ala and Met,A1 to A20 or B2 to B29 are the amino-acid sequence of human or animal insulins. 3." . . . .