Could u know dominance/recessive by knowing the base sequence?

Question

if u got a normal gene and a mutant form of it, could u know if the mutant is dominant or recessive by knowing the nulceotide sequence?

Answer 1

In general, no. There are special cases though. For example, if the mutation is something that results in a missing or useless protein, via a premature stop codon (nonsense mutation) or if the start codon is changed, this can be recognized by the nucleotide sequence. The mutation in these cases would be considered recessive because the phenotype would be governed by the other allele. Be careful about the nonsense mutation though. If enough of the protein is left intact, it could potentially act as a dominant negative depending on how the protein works....