One way mutations can affect the phenotype is by altering th

One way mutations can affect the phenotype is by altering the coding sequence of a gene and therefore changing protein structure. Please describe two ways that mutations can affect the phenotype that does not include alteration of the protein coding sequence

Solution

Silent mutations can occur in non-coding regions i.e,outside of genes or within introns,or they may occur within exons.When they occur within exons they either do not result in a change to the amino acid sequence of a protein.Silent substitutions never alter the amino acid sequence of the polypeptide chain.

The other type of mutations is regulatory point mutations which include   mutations in promoter,polyadenylation,mutations in splice site,DNA replication mutation.

The effect of mutations in the promoter causes Changes timing or amount of gene transcribed.
The effect of mutations in polyadenylation alters sequence of mRNA, may affect mRNA stability.
The effect of mutations of the splice site may retain intron sequence in or exclude exon sequence from mature mRNA.
The effect of DNA replication mutations   increases or decreases(less often) number of repeats of DNA triples,causing instability of mRNA or incorrect number of repeating amino acids.