Author Topic: Identical Twins  (Read 699 times)

Offline jim234j

  • RootsChat Senior
  • ****
  • Posts: 270
  • Census information Crown Copyright, from www.nationalarchives.gov.uk
    • View Profile
Identical Twins
« on: Monday 10 July 23 19:03 BST (UK) »
My wife is a Identical Twin and had her DNA done.
Her Identical Twin sister did not have her DNA done but her son did.

Here is the result when you compare their DNA which makes sense . (Ancestry)
Son | Both sides50% shared DNA: 3,417 cM across 31 segments

If my wife's Identical twin sister had her DNA done and my son also  did would both sons end up with two mothers DNA wise and would they be half brothers?  :)

Jim

Online KGarrad

  • RootsChat Marquessate
  • *******
  • Posts: 25,973
  • Census information Crown Copyright, from www.nationalarchives.gov.uk
    • View Profile
Re: Identical Twins
« Reply #1 on: Monday 10 July 23 19:21 BST (UK) »
The only DNA tests my family have done are zygosity tests, on my daughters and granddaughters! Both sets were proved to be identical twins.l

No need for any other DNA tests ;)

My brother and I are fraternal twins - so not identical.
Garrad (Suffolk, Essex, Somerset), Crocker (Somerset), Vanstone (Devon, Jersey), Sims (Wiltshire), Bridger (Kent)

Offline Janelle

  • RootsChat Member
  • ***
  • Posts: 205
    • View Profile
Re: Identical Twins
« Reply #2 on: Tuesday 11 July 23 04:06 BST (UK) »
The children of 2 mothers who are identical twins are half siblings for their DNA because they have different fathers

Offline LizzieL

  • RootsChat Marquessate
  • *******
  • Posts: 7,855
  • Census information Crown Copyright, from www.nationalarchives.gov.uk
    • View Profile
Re: Identical Twins
« Reply #3 on: Tuesday 11 July 23 08:18 BST (UK) »
My grandfather had an identical twin brother. The grandson of this twin brother and I share 406 cM which is more consistent with us being half first cousins instead of 2nd cousins which we really are.
Berks / Oxon: Eltham, Annetts, Wiltshire (surname not county), Hawkins, Pembroke, Partridge
Dorset / Hants: Derham, Stride, Purkiss, Sibley
Yorkshire: Pottage, Carr, Blackburn, Depledge
Sussex: Goodyer, Christopher, Trevatt
Lanark: Scott (soldier went to Jersey CI)
Jersey: Fowler, Huelin, Scott


Offline LizzieL

  • RootsChat Marquessate
  • *******
  • Posts: 7,855
  • Census information Crown Copyright, from www.nationalarchives.gov.uk
    • View Profile
Re: Identical Twins
« Reply #4 on: Tuesday 11 July 23 08:23 BST (UK) »
The children of 2 mothers who are identical twins are half siblings for their DNA because they have different fathers

But what if identical twin sisters married identical twin brothers ? ;D
Their offspring would appear to be full siblings according to their DNA.
I wonder if it has ever happened?
Berks / Oxon: Eltham, Annetts, Wiltshire (surname not county), Hawkins, Pembroke, Partridge
Dorset / Hants: Derham, Stride, Purkiss, Sibley
Yorkshire: Pottage, Carr, Blackburn, Depledge
Sussex: Goodyer, Christopher, Trevatt
Lanark: Scott (soldier went to Jersey CI)
Jersey: Fowler, Huelin, Scott

Offline bearkat

  • RootsChat Marquessate
  • *******
  • Posts: 7,581
    • View Profile
Middx - VAUS, ROBERTS, EVERSFIELD, INMAN, STAR, HOLBECK, WYATT, BICKFORD, SMITH, REDWOOD
Hants - SMALL, HAMMERTON, GRIST, FRYER, TRODD, DAGWELL, PARKER, WOODFORD, CROUTEAR, BECK, BENDELL, KEEPING, HARDING, BULL
Kent - BAYLY, BORER, MITCHELL, PLANE, VERNON, FARRANCE, CHAPMAN, MEDHURST, LOMAX, WYATT, IDEN
Devon - TOPE, BICKFORD, FOSTER
YKS - QUIRK, McGUIRE, BENN
Nott/Derbs - SLACK
Herts - BARNES
L'pool- PLUMBE
 All UK census information Crown Copyright, from www.nationalarchives.gov.uk

Offline Cell

  • RootsChat Aristocrat
  • ******
  • Posts: 1,696
  • Two words that can change the world "Thank You"
    • View Profile
Re: Identical Twins
« Reply #6 on: Tuesday 11 July 23 10:48 BST (UK) »
Yes  its a  very, very  huge probability your son and his cousin will be most definetely shown  as half brothers and your wife's  sister will also be shown as your son's  mother as too your wife  - two mothers ( which I think they will be if  your son was to test ) .

I share with my child just a little bit  more than your wife and her nephew does ,  but  not  a huge  amount more ( I share 3527 ) .  And  share 50% with my child of course.

I  really  don't  think  commercial  companies  such as Ancestry  and so on can tell the difference  which is  the parent when they are identical twins with a simple  one for all spit test  .   There has been many of a case   this when  it comes to twins .

Is your wife's  sister  alive  and willing to take a DNA test ?  And is your son willing  to take a dna test too?  I  think they ( the two cousins)  will shown  as half brothers ( quite  easily!! )

 my  half uncle , it is shown  I could  be his half sibling lol    ,  or a full  cousin, or his full niece (it all falls In within the high amount shared DNA   I  share with  him. I am 100% definitely his  half niece and not a half sibling , or otherwise (  and no twins  involved)

 Fascinating
Kind regards :)
Census information in my posts are crown copyright www.nationalarchives.gov.u

Offline jim234j

  • RootsChat Senior
  • ****
  • Posts: 270
  • Census information Crown Copyright, from www.nationalarchives.gov.uk
    • View Profile
Re: Identical Twins
« Reply #7 on: Tuesday 11 July 23 16:41 BST (UK) »
Thank you for all your replies.

My wife's sister and my son are willing to take tests and will likely do so when there is a sale.

When my nephew got his results showing my wife as his mother he asked his mother if there was something she was not telling him.   Ha.



Online Glen in Tinsel Kni

  • RootsChat Aristocrat
  • ******
  • Posts: 1,197
  • Scottish Borders
    • View Profile
Re: Identical Twins
« Reply #8 on: Wednesday 12 July 23 16:30 BST (UK) »
Whilst there are actually two samples from two different individuals the dna of identical twins is identical. As there is nothing to distinguish one from the other they are in essence a duplicate sample from the same person for testing purposes.