Meiosis in cell with odd diploid number

[stfz]

I've come across a question which is asking what would happen in a cell with odd diploid number 2n=15 when it undergoes meiosis. Here's my thinking:
- 15 chromosomes, so 7*2 homologues + 1 loner?
- Hence, after Meiosis I, we'd have 7 chromosomes in one cell, and 8 in the other?
- After meiosis II, we'd have 2 cells with 7 chromosomes, and 2 cells with 8?

Just wanted to check that this is a plausible answer for this situation? It seems a bit rare, and odd 2n appears to be associated with infertility (e.g. mules).

Would appreciate a confirmation of this :) Thanks!

 

[Megaquark]

An odd number of chromosomes is often the result nondisjunction...the chromosomes don't separate properly. The term aneuploidy is used for such an abnormal number of chromosomes. Many genetic disorders are associated with odd numbers of chromosomes. Down's syndrome in humans for example...but there are also examples of people who have extra sex chromosomes who live normal lives...XXY trisomy for example.

 

[jim mcnamara]

@Megaquark is correct - that example is NOT diploid. And since you see why meiosis has problems, aneuploid organisms, if they live long enough to attempt reproduction, have serious issues with fertility. They cannot create viable gametes generally.

 

[jim mcnamara]

FWIW - thought about adding something in terms of human genetics - maybe Turner's Syndrome? - aneuploidy involving the X chromosome.
https://en.wikipedia.org/wiki/Turner_syndrome