Answer:
b.c d are the answer options
Explanation:
b. The recessive allele could be a mutation in the promoter region that prevents RNA polymerase II from binding.
c. The recessive allele could be a mutation in the transcribed region that makes the mRNA unstable and causes it to degrade.
d. The recessive allele could be a mutation in regulatory DNA that prevents chromatin from being remodeled from a closed to an open state.
in option b, the synthesis of mRNA is going to be halted
in option c, mRNA is undergoing degradation, it will be invisible in the northern blot.
in option d, mRNA in expression of each gene is going to be turned off.
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