Step Twin

[Seasrmar]

Hi everyone, I don't know much about Biology, even less in Genetics. So what I am about to ask may sound stupid, but I'm really curious, but please hear me out.

Hypothetical situation, a male is with two females who are identical twins. If I am correct, identical twins have very close identical DNA. So if the male got the two females pregnant and transfer the same genetic materials in making the babies. And the sperms and eggs developed the same way. Could the two babies born of two identical twins females with the same genetic materials from the same male, be like step twin?

[JackBean]

don't look so much to porn

Well, each sperm of the male contains different set of his maternal/paternal chromosomes (and they can be even combined, like half chromosome from mother and the other half from father), so the kids would not be identical.

(but BTW the identical twins have the same DNA, that's why are they identical;)

[Seasrmar]

I assure you, it's not porn related; pure academic interest for a hypothetical situation. Some cultures practice sororal polygyny- marriage in which the wives are sisters. The sisters can be identical twin.

Thanks for answering my question though. If I may expand on it further. Isn't there a chance that two or more sperm be a like ie: carry the same genetic materials. As you say, it can carry the male's father, mother, or a combination of both. Ok, regardless of which one of the above, can two sperm be a like ie: both carry only male's father, mother, or same combination of both. Now combine with the twin. Voila, step twin.

[JackBean]

well, you have approx. 3.10^9 bp in 23 pairs of chromosomes (taking X and Y as a pair;), so you can have 2^23 possibilities, how to combine your chromosomes and than theoretically 3.10^9 possibilities of crossing-over. Of course, you have several billions (or what are the numbers in English) of sperms only in one shot ( ), so count it by yourself, what is higher number

[canalon]

Are two siblings identical?
Because their parents have the exact same genetic make-up, and yet no one have a problem to pinpoint who is who in the family

[JackBean]

IMHO that's kind of "parent's sense", because other people can be easily confused usually

[Seasrmar]

I like my odds.

[JackBean]

BTW you can't forget, that the twins have identical DNA, but DNA in their eggs won't be identical, right?
*So, the chance of them getting the same DNA subset is the same as for yours two sperms;)

[fastsandslash]

Now, actually this is possible. Some prerequisites involve:
Identical twins or sisters with at least enough identical DNA to produce an egg each, of which contain identical DNA.
A father, frick god, who can produce at least two identical sperm which at least one reaches each egg before all other sperm.

The odds of that would be less than winning Lotto Powerball 800,000 times consecutively. If this did happen, God call me rich XDDDD!!!

[JackBean]

yeah, I guess that has been said before