I'm pretty sure that cells contain genes inside them.
Answer:
The promoter region/sequence
Explanation:
Promoter sequences/region is where the transcription factors and RNA polymerase must attach before the gene can be transcribed. SO if we mutate this sequence, the transcription factors and RNA polymerase won't recognize it thus would not attach and transcribe the targeted gene.
DNA, Chromosomes, Nucleus, Cell, Organism
Explanation:
DNA makes up the Chromosomes, which are stored in the nucleus, which is the brain of the cell, and cells make up organisms.