Title 16, Chapter 6, Section 22
(a) A person commits the offense of incest when he engages in sexual
intercourse with a person to whom he knows he is related either by
blood or by marriage as follows:
(1) Father and daughter or stepdaughter;
(2) Mother and son or stepson;
(3) Brother and sister of the whole blood or of the half blood;
(4) Grandparent and grandchild;
(5) Aunt and nephew; or
(6) Uncle and niece.
(b) A person convicted of the offense of incest shall be punished by
imprisonment for not less than one nor more than 20 years.