In a person with the genotype XXY, we can tell that nondisjunction took place in the mother.

Question

Quizplus · Accepted Answer

It is impossible to determine whether nondisjunction occurred in the mother or father based solely on the genotype of the offspring. Nondisjunction can occur during either the meiosis I or meiosis II division in either parent, resulting in a gamete with an extra chromosome. Therefore, it is not accurate to assume that nondisjunction occurred in the mother simply because the offspring has a XXY genotype.

In a Person with the Genotype XXY, We Can Tell