Alright, I was bored out of my mind at work. I’m a student worker that is in charge of sanitizing student use computers and helping students if they need assistance with stuff. Trust me, it gets a little boring. Well, today there is literally no one in here accept a fellow student worker that is as talkative as a head of cabbage… so I went about thinking stuff… the thing that popped into my head was the episode of Futurama when Philip Fry and the crew got sucked into the past as the Rosewell alien crash. ‘Rosswell That Ends Well’ which originally was supposed to be called "The Y of Fry".

Anyway, the part that concerns this post comes from the DVD commentary as an explanation on the title of the episode. The writer/producer said ‘if what we’ve set up is true, where fry’s Y chromosome come from?” Well… if you’ve done 8th grade life science you probably understand Punnet Square. If you don’t read the next paragraph, if you do SKIP IT :P

Punnet Squares are a way to track a genetic trait (for this moment we’re talking gender). In a normal genetic human male, they possess a pair of chromosomes XY, a normal genetic female is XX. In paring these in a Punnet Square you can see the outcome of XX, XX, XY, XY; which results in equal odds of offspring being either male or female (and in real birth rates, is almost accurate).

In order for Fry to have a normal XY chromosome, there would have to be some genetic damage in the past. The easiest way to set it up was to consider Fry’s genetic code XY tracked as an AB pair and genetically damage his grandmother a Klinefelter Syndrome individual XXY CD that was denied the testosterone bath during the first trimester (the XY determines the genetic sex, but the mothers hormones are triggered by the XY pair to give a high testosterone level resulting in the males development). If he was to go into the past and have offspring with his grandmother (as the series states), the resulting child would have to be a genetically damaged SuperMale XYY DB.
This is where it gets a little tricky, in order for Fry to recover his original X A female strand, his mother XX AC would have to be related directly to Fry’s father, given that we don’t know if Fry’s mother and father are related directly, for simplicity sake we can say that Fry’s grandmother had a genetically normal female child by another genetically normal male XY MN, resulting in Fry’s Mother XX AM.
Now, Fry’s mother XX AM and Fry’s SuperMale Father XYY DB could result in four potential outcome genders, however for Fry’s genetic code to be reassembled, he would have to be the result of an XY AB and not an XY BM. Fry as an XY AB is then recycled back into the genetic stranding to result in his genetic code all over again.
However, looking at this, you find that the X A in his genetic code is introduced by himself. Meaning that the X A half of his genetic code creates the paradox.

Just remember… I’m not a geneticist… just a student with nothing to do accept clean computers for four hours.
Yarg… I way over think things when bored out of my skull at work. XD!