What would cause a person to have two copies of the bent thumb allele (tt)? 1. A person whose mother or father had two copies of the bent thumb allele will always have two copies of the allele.

2.A person with two copies of "t" inherited one from their mother and one from their father.

3. A person born with one "t" mutation is more likely to develop a second "t" mutation during their lifetime.

4. A person with two copies must have duplicated the "t" allele through mitosis early in development. (They inherited one, then doubled it)