Fourteen of 27 amino acids of secretin reside in the same positions as in glucagon, 7 the same as in VIP, and 10 the same as in GIP.
Dos 27 aminoácidos da secretina, 14 están situados na mesma posición ca os do glicagón, 7 na mesma ca os do VIP, e 10 na mesma ca os do GIP.