1.连续性、方向性 Second base c A G A frameshift mutation UUU UCU UAU UGU inserts a new basepair here. Phe 公 Cys Normal DNA UUC ucc UAC UGC Ser ATGACCTTTGATCTAAAG ATGAACCTTTGATCTAAAG UUA UCA UAA Stop UGA Stop Leu 9 TACTGGAAACTAGATTTC DNA UUG UCG UAG Stop UGG Trp CUU cCU CAU CGU strand His Transcription CUC ccc CAC CGC . Leu Pro Arg CUA Reading frames CCA CAA CGA 9 CUG CCG CAG CGG G AUGACCUUUGAUCUAAAG mRNA UGAUCUAAAG First base Third base AUU ACU AAU AGU Asn Ser codor AUC ACC AAC AGC Translation .and new reading frame A ensues in translation. AUA ACA AAA AGA Lys Arg AUG Met/Start ACG AAG AGG Thr Leu Lys Protein GUU GCU GAU GGU Asp GUC GCC GAC cac 0 Frameshifts often lead to G Val Ala Gly premature termination. GUA GCA GAA GGA Glu GUG GCG GAG GGG 1. 连续性、方向性