<span>Some mutations don't have any noticeable effect on the phenotype of an organism. This can happen in many situations: perhaps the mutation occurs in a stretch of DNA with no function, or perhaps the mutation occurs in a protein-coding region, but ends up not affecting the amino acid sequence of the protein.</span>
I think the first think that you should <span>check if the numeric keypad on a standard desktop keyboard is not working is the num lock key. This key controls whether the primary function of the numeric keypad or the secondary function will work when pressed. </span>