(a) A person commits incest who engages in sexual penetration as defined in § 39-13-501, with a person, knowing such person, to be, without regard to legitimacy:
(1) The person's natural parent, child, grandparent, grandchild, uncle, aunt, nephew, niece, stepparent, stepchild, adoptive parent, adoptive child; or
(2) The person's brother or sister of the whole or half-blood or by adoption.
(b) Incest is a Class C felony.