Second position U C A G UCU UAU JGU U Phe Tyr Cys uuc ucc UAC UGC Ser UCA UAA Stop UGA Stop A Leu UUG UCG UAG Stop UGG Trp G CUU CCU CAU CGU His cuc CCC CAC CGC Leu Pro Arg CUA CCA CAA CGA GIn cuG ccG CAG CGG AUU ACU AAU AGU Asn Ser AUC ACC AAC AGC Thr AUA ACA AAA AGA 减少了变异对生物的影响 Met ACG AAG AGG GUU GCU GAU GGU Asp GUC GCC GAC G G Val GUA GCA Ala Gly GAA GGA GUG GCG GAG GGG减少了变异对生物的影响