Identical twins + Identical twins = ?

[jamie1985]

Quick question thats bugging me while i'm bored at work,

If two male identical twins reproduced with two female identical twince [separately of course] would their chrildren be amazingly alike? :confused:

[jamie1985]

damn no 'edit feature' and i've re-drafted the English spelling of twince to twince.

[Q.E.D.]

No more so than other siblings. They would, however, be more likely to have twins themselves than typical couples.

[Shagnasty]

No, probably not but the children would be brother and sister genetically.

[jamie1985]

OMG, i'm on damn drugs!!!! TWINS!!!

[Q.E.D.]

Oh, and welcome to the SDMB, jamie1985. Enjoy your stay here. :)

[sugaree]

Originally posted by Q.E.D.
No more so than other siblings. They would, however, be more likely to have twins themselves than typical couples.

I thought that fraternal twins were genetic, but identical twins were just an egg that happened to split.

[jamie1985]

Thanks Q.E.D :)

And BTW in my 3 weeks as a lurker i've decided to believe Zotti = Cecil

[Enderw24]

Get your stinkin drugs off me you damn dirty twins!!!

Every sperm is different (and sacred). Every egg is too. There are literally hundreds of millions of different combinations that can be had every single time you have sex with someone.

So, as Shagnasty said, they would be brother and sister genetically. The odds of producing the exact same child in both sets of twins would be so fantastically remote it would practically be zero.

[sugaree]

:eek:

[Q.E.D.]

Originally posted by sugaree
I thought that fraternal twins were genetic, but identical twins were just an egg that happened to split.
They are. The OP is asking about the offspring of two couples of identical twins.

[sugaree]

The :eek: was not at Ender's stats, but was meant to convey my shock and horror at hearing the sacred name of Cecil associated with that of Zotti.

::reels away, fanning herself:::

QED, my question is do identical twins run in families? I thought that the condition was not genetic. If that's true, why would identical twins have a higher chance of having twins?

[Nametag]

Identical twins run in families because the "weakness" that causes the egg to split after dividing is genetic. Sometimes it's just happenstance, though. Similarly, the production of multiple ova can be genetic, drug-induced, or just happenstance.

[toadspittle]

quote:
------------------------------------------------------------------------
Originally posted by sugaree
I thought that fraternal twins were genetic, but identical twins were just an egg that happened to split.
------------------------------------------------------------------------
They are. The OP is asking about the offspring of two couples of identical twins.

I assume sugaree is questioning: "They would, however, be more likely to have twins themselves than typical couples."

So the question is do identical twins (the result of a zygote that split completely) have a greater tendency to produce identical twins than the non-twinned populace (i.e., do their zygotes have a greater tendency to split)? Or is it people who are fraternal twins (the result of two completely different eggs being fertilized by two different sperm) that have a greater propensity to have twins? Or is it all just a bunch of hooey that twins are more likely to give birth to twins? (Or is it just female twins ... since it's their splitting eggs and double-shooting ovaries at work...?)

[sugaree]

Originally posted by Nametag
Identical twins run in families because the "weakness" that causes the egg to split after dividing is genetic. Sometimes it's just happenstance, though. Similarly, the production of multiple ova can be genetic, drug-induced, or just happenstance.

Oh. In that case, identical twins would be more likely to concieve other identical twins, and wouldn't be at greater odds to concieve fraternal twins unless that also ran in the family?

[Biggirl]

Here is a site that shows Twin basics. (http://mypage.direct.ca/c/csamson/multiples/twinbasics2.html)

If You Are A Twin (Or Have Twins In Your Family):

If you are a fraternal twin, you have a 1 in 17 chance of having twins. If you are identical, it doesn't affect your chances, and they remain from 1 in anywhere from 38 - 90, depending on if fertility drugs are used or not. If your mother is a fraternal twin, you may have a higher than average chance of twins. If you father is a twin, it doesn't affect your chances, as fraternal twinning is apparently carried down the maternal line. If your husband is a twin or has twins in his family, it doesn't affect your chances of having twins.

If you have a parent that is an identical twin, your chances of having twins yourself are the same as anyone else.

[Meatros]

Originally posted by Nametag
Identical twins run in families because the "weakness" that causes the egg to split after dividing is genetic.

Really? I didn't know that identical twins run in families. I'm an identical twin and I can't think of anyone else in my family having a twin (then again I don't know all of my extended family).

[John Mace]

Re: genetic dependence of identical twins. Does anyone know if it matters whether the twin is on the mother's or father's side? Since the mother contributes more than just chromosomes (the mtDNA and the cytoplams and the rest of the egg cell), I'm wondering if that has any effect.

[jct103]

:cool: I can see why you're asking this question - at the moment the egg splits identical twins have exactly the same genetic makeup, after which the environment influences and small changes occur. It seems that what you are getting at is that the the two couples having one child each is the same as one couple having two children. However. I have 3 siblings and we don't look alike at all!!

[Biggirl]

I am the mother of fraternal twins. My daughter's chances of having twins is greater than the general population. My son's chances of having twins is the same as the general population.

My chances of having twins (before I gave birth to twins) was the same as the general population-- I say this because I am both black and Hispanic, blacks have a higher incident of twinning while Hispanics have a lower incident of twinning. So it's was a wash. Once I gave birth to those little buggers, my chances of having more twins jumped.


If my kids had been identical, then all of the above goes out of the window. It's a crap-shoot and everybody's got the same chance. Egg weakness is a new one on me. Although it is plausible, the numbers indicate that identical twinning is random.

Sooooo. The identical twins chances of having identical twins is the same as anybody else's chance of having identical twins.

[Nametag]

Well, it doesn't run as much as fraternal twins do, and I'd guess the splitting is still a matter of some "luck" even in those who are predisposed. Certainly it's not a significant part of the identical twin population, but there are some families where in which identical twins seem to run.

[Nametag]

I should also mention that, occasionally, an egg will split (with its polar body, I think) and be fertilized by two different sperm. These are called polar body twins or some variation on identical twins. The shared genetic material between such twins is between 50% and 75%, and it definitely runs in the family - the mother's family, as the characteristic of egg-splitting is genetic.

[Turek]

Originally posted by Nametag
Identical twins run in families because the "weakness" that causes the egg to split after dividing is genetic.

I have friends who are twins, who also have twin sisters. Their mom might have the "weakness" you describe, but she must also have a ton of patience.

[aahala]

Sidebar - The offspring between the two couples would be double cousins and ignoring the twins aspect, it was fairly common in the 1800s. This makes for an interesting looking family chart.

[davesink]

Originally posted by Meatros
Really? I didn't know that identical twins run in families. I'm an identical twin and I can't think of anyone else in my family having a twin (then again I don't know all of my extended family).

Uh...how bout your brother/sister?;)

[drpepper]

I want to make sure I have this straight:

Fraternal twinning is linked with a gene and may "run in families", as it were.

Identical twinning is not.

Is this right? Does everyone agree with this?

[Meatros]

Originally posted by davesink
Uh...how bout your brother/sister?;)

None in his family either...:D


Aside from my brother and I, there are no other twins.

[Biggirl]

Originally posted by drpepper
I want to make sure I have this straight:

Fraternal twinning is linked with a gene and may "run in families", as it were.

Identical twinning is not.

Is this right? Does everyone agree with this?

If you could get everyone to agree with something-- anything on this board, you should get some sort of prize. But yes, this is the general understanding in the medical community.

[rocking chair]

i can't believe no one starting the singing yet.... so i guess i will. ah hem... meee,eee,eee meeee.

cousins, identical cousins....

[Scruloose]

Originally posted by jamie1985
Thanks Q.E.D :)

And BTW in my 3 weeks as a lurker i've decided to believe Zotti = Cecil

Or perhaps Cecil and Ed are the siblings of two pairs of identical twins who decided to marry.... :dubious:

[Bob55]

The children would look different due to the randomness of recombination during meiosis - but they would probably look like siblings.

[Enderw24]

Oooh oooh! Here's something funny I just thought of.

If a set of identical female and identical male twins had an orgy, there would be no way to figure out who the fathers are when both females give birth.

[bcullman]

Identical twins + Identical twins = ?

Originally posted by Shagnasty
No, probably not but the children would be brother and sister genetically.

whoa -

is this true?

[II Gyan II]

Originally posted by jamie1985

And BTW in my 3 weeks as a lurker i've decided to believe Zotti = Cecil

[hijack]

If you look at any Staff Report (http://www.straightdope.com/mailbag/mwashboard.html), it says at the bottom

Although the SDSAB does its best, these articles are edited by Ed Zotti, not Cecil, so accuracywise you'd better keep your fingers crossed.

Why this disclaimer ? To throw us off track ? :dubious: