title: On the nature of mutations in molecular evolution.
abstract: In this work it is proposed tht in evolution amino acid substitutions implying strong physico chemical and structural differences are more revelant and more frequent that substitutions between similar amino acids.  This analysis is made over a group of protein families representing about 10000 substitutions and as examples the evolutionary trees of fibrinopeptides A and calcitonins were constructed and compared.
authors.affiliation: Departamento de Física, Universidad de Chile, Santiago.
authors.forename: M A
authors.initials: MA
authors.lastname: Soto
authors.forename: J
authors.initials: J
authors.lastname: Tohá
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry / Q000235:genetics*; D000818:Animals; D002116:Calcitonin / Q000737:chemistry / Q000235:genetics*; D019143:Evolution, Molecular; D005344:Fibrinopeptide A / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D009154:Mutation; D017354:Point Mutation; D011506:Proteins / Q000737:chemistry / Q000235:genetics
chemical_list: D000596:Amino Acids; D011506:Proteins; D005344:Fibrinopeptide A; D002116:Calcitonin