Chapter 4, Problem 25P

Women sometimes develop benign tumors called ovarian teratomas or dermoid cysts in their ovaries. Such a tumor begins when a primary oocyte escapes from its prophase I arrest and finishes meiosis I within the ovary. (Normally meiosis I does not finish until the primary oocyte is expelled from the ovary upon ovulation.) The secondary oocyte then develops as if it were an embryo. Development is disorganized, however, and results in a tumor containing differentiated diploid tissues, including teeth, hair, bone, muscle, and nerve. If a dermoid cyst forms in a woman whose genotype is Aa, what are the possible genotypes of the cyst, assuming no recombination?