Boy-girl twins fact poll

[RegGuheert]

DD10 an DS10 are twins. I am wondering what the level of knowledge regarding boy-girl twins is. Please answer the poll with your first reaction and without googling.

 

Thanks for indulging me!

[RoughCollie]

If anyone here needs to Google this, I'll be surprised.

[Angie in VA]

If anyone here needs to Google this, I'll be surprised.

 

Thank you.

[RegGuheert]

If anyone here needs to Google this, I'll be surprised.

C'mon, RoughCollie, you KNOW you want to Google it! (And so does WendyK who liked your post!) ;)

[RegGuheert]

I didn't google it. I don't see how they could be one of those choices (don't want to give it away).

Would you like me to add an 'Other' option to the poll? (After all, I violated the cardinal rule of WTM polling!)

[RegGuheert]

Would you like me to add an 'Other' option to the poll? (After all, I violated the cardinal rule of WTM polling!)

I'll take it you want me to edit the poll since you liked the post. I'll do it, but only if it won't erase everyone's votes. I know on other forums I visit editing a poll does that. Does anyone know if I can add another option without losing the results?

[flopsymopsy]

I have a twin brother and believe me.......I get the poll!

[NotSoObvious]

I had a friend with b/g twins and people asked of they were identical ALL the time. She used to say, "yeah, except for the p*nis."

[JVA]

We have b/g twins and got this question when they were infants. I was shocked then. Our daughter (they're 30) now still gets surprised when people ask if they're identical. I chalk it up to another failure of public education. :glare:

[history_junkie]

Umm, google gives different answers. After watching some DVDs on multiples my mom realized that knowledge has changed since her nursing school days...

[fairfarmhand]

I had a friend with b/g twins and people asked of they were identical ALL the time. She used to say, "yeah, except for the p*nis."

We have b/g twins and got this question when they were infants. I was shocked then. Our daughter (they're 30) now still gets surprised when people ask if they're identical. I chalk it up to another failure of public education. :glare:

 

perhaps this could be the oblivious people who assumed that my PINK LACY DRESSED babies were boys and my guy wearing blue and a ball cap was a girl. ???

[RegGuheert]

We have b/g twins and got this question when they were infants. I was shocked then. Our daughter (they're 30) now still gets surprised when people ask if they're identical. I chalk it up to another failure of public education. :glare:

This was always my feeling, as well.

 

But then our oldest grew up and went to college and took it upon himself to fact-check everything MomsintheGarden and I said. :glare:

 

The short of it is that since the term "fraternal twins" is synonymous with "dizygotic twins," the second option in this poll is NOT a correct response.

 

We can argue whether or not the third option is correct or not, but since "identical twins" is used to mean "monozygotic twins" in common parlance and monozygotic boy-girl twins have recently been identified, I will put forth that it is the most correct response.

 

It is also correct to say that monozygotic boy-girl twins are not genetically identical since there are chromosomal differences.

[Hwin]

I saw on a TLC show where they made a case for b/g identical twins (if the egg splits at exactly the right moment...) but I don't consider different genitalia identical.

[Matryoshka]

I saw on a TLC show where they made a case for b/g identical twins (if the egg splits at exactly the right moment...) but I don't consider different genitalia identical.

 

So, since the original cell has either XX or XY sex chromosomes, how exactly does the one of the embroys manage to gain/lose an X or Y chromosome if it splits "at the right time"? That makes no sense. What is the biology?

 

I was thinking it would be possible to have identical boy/girl twins if there was a catastrophic circumcision accident on b/b twins and there had to be surgery on one... but that's different. ;)

[RegGuheert]

I saw on a TLC show where they made a case for b/g identical twins (if the egg splits at exactly the right moment...) but I don't consider different genitalia identical.

Nor do I. But neither do I define "identical twins" as two identical people. Contrary to popular belief, a person's structure is not fully defined by their genome. Environment plays a role in how they form, as well.

So, since the original cell has either XX or XY sex chromosomes, how exactly does the one of the embroys manage to gain/lose an X or Y chromosome if it splits "at the right time"? That makes no sense. What is the biology?

My understanding from reading is that there are two different mechanisms for this phenomenon to occur:

 

1) An egg containing X,X and Y chromosomes splits into one containing X and Y and another containing X and Y.

2) An egg contains X and Y chromosomes splits into two parts, each with X and Y, and then one of them loses their Y chromosome, becoming a girl with Turner's syndrome.