its the person's offspring have mutated skin.
because for a mutation to be passed down to an offspring mutation has to happen in the sex cells. so that is the least likely to happen.
since the other may happen for example.
skin cancer: i am not sure how but definitely sure that it is the second least that is gonna happen. (trust me)
reduced functioning of skin cell yes.: if there are changes in the nucleotides which can give a diff amino acid.
and no change. cuz if the mutation occurs but the nucleotides still codes for the same amino acid then there is no problem!!