Answer:
Step-by-step explanation:
Three ways in which mutation could occur are
1) If an error occurs during DNA replication and it's not corrected in time by DNA polymerase.
2) If there is a deletion of a base(s) in the sequence of the DNA. The deletion of a DNA nucleotide/base could also cause a mutation as that could affect the formation of an enzyme or protein useful in building and/processing certain body parts/processes.
3) Thymine dimerization: Thymine dimers are mutations that prevent DNA from replication or even transcription hence preventing a cell from undergoing division (hence causes cancer). They are formed when covalent bonds are formed between the bases of a DNA sequence (somewhere around the carbon-carbon double bond).
The two effects are
1) It could cause cancer as described in (3) above (in the case of thymine dimer)
2) It could lead to deformity in an individual because of the gene that is supposed to code for the last finger has a base deletion, that could eventually lead to the absence of that finger or a shorter or "strange" finger.