Something that go against genetic !!!!

[chuinhen]

If They are 2 identical female Twins from Family A

 

and 2 identical Male twins from Family B ...

 

If both of the sister marry the both brothers

 

and one of the couple gave birth first ..

 

 

My question is ...if the other couple claims that the baby is their's

how are we going to solve this Havoc ??

[Royston]

If They are 2 identical female Twins from Family A

 

and 2 identical Male twins from Family B ...

 

If both of the sister marry the both brothers

 

and one of the couple gave birth first ..

 

 

My question is ...if the other couple claims that the baby is their's

how are we going to solve this Havoc ??

 

Well this doesn't really go against genetics. Errr, I'm not sure why you mentioned 'one of the couple gave birth first'...if the other twin is still pregnant then that kinda puts an end to it.

 

If the babies were born around the same time...and then switched at the hospital, and then there was confusion as to who's baby's was who. That may cause problems...I don't know enough about DNA and twins, and if there would be a problem identifying who's baby was who's...someone else may be able to answer that.

[Dak]

If They are 2 identical female Twins from Family A

 

and 2 identical Male twins from Family B ...

 

If both of the sister marry the both brothers

 

and one of the couple gave birth first ..

 

 

My question is ...if the other couple claims that the baby is their's

how are we going to solve this Havoc ??

 

look for stretch-marks on female twins to establish which one's given birth.

 

other than that, identical twins aren't identicle due to post-fertilisation recombination, so i suppose you could isolate individual chromosomes, analyse them and figure it out like that probably.

[Immunologist]

From a genetic point of view, the somatic (non-gametes) cells of twins bear the same genetic background. We agree on this.

 

However, twins don't necessary have the same genetic information in their gametes (eggs of spermatozoids) as mutations can occur when creating the gametes...

 

So there is a possibility that by analysing the 2 couples gametes, you find a mutation... the presence or absence of this mutation in the child somatic cells could identify the parents.

 

See ya!

[Nashyboyo]

the DNA markers present in both kids parental chromosomes and both kids maternal chromosomes are 99.999% likely to be the same as the father and mother respectively but the brothers and sisters have equal DNA sequences to each other. so it wouldn't be possible to determine which is which without looking at the physical traits and phenotypes of each of the family histories and comparing them to physical traits and phenotypes in each child.

[Y-S]

perhaps some pedigrees would help.......

[Immunologist]

the DNA markers present in both kids parental chromosomes and both kids maternal chromosomes are 99.999% likely to be the same as the father and mother respectively but the brothers and sisters have equal DNA sequences to each other. so it wouldn't be possible to determine which is which without looking at the physical traits and phenotypes of each of the family histories and comparing them to physical traits and phenotypes in each child.

 

Wait, if the DNA sequences are the same then the ancestry is totaly pointless as they are starting with the SAME background. Variations in the phenotype will be due to environmental factors affecting development after conception.

Yes I agree DNA would be 99,999% identical, therefore markers are unable to make the difference (well, improbable). It is why a sequencing (whole genome) would be necessary to identify small mutations (1 nt to few nts) that are found in parental gametes and in child somatic cells. Actually, it would cost thousands to do such things, but as far as I am aware the question was theoric.

 

Phenotypic analysis and family histories are irrelevant as both genitors are identicals.

[Nashyboyo]

ah yeah. i was pretty stoned when i wrote that

[Dark Photon]

well you would only be able to distinguish if anything by enviromental factors. the likley hood of such a event is quite low

[DaveC426913]

If They are 2 identical female Twins from Family A

 

and 2 identical Male twins from Family B ...

 

If both of the sister marry the both brothers

 

and one of the couple gave birth first ..

 

 

My question is ...if the other couple claims that the baby is their's

how are we going to solve this Havoc ??

The one with the deflated belly is the owner of the baby. The one with the bulging belly is not.

 

There must be more to this...

[chuinhen]

Deflated Belly ?? If it is after birth or after 10 years ??

[Dak]

I think this would work:

 

OK, two gametes form a zygote:

 

|X

|X

|X <--this is a diploid zygote, OK

|X

 

 

then, it duplicates. these will eventually form 'identicle' twins, so we can think of these as the genomes of the two twins:

 

A..............B

 

|X............|X

|X............|X

|X............|X

|X............|X

 

 

Then, post-fertilisation recombination occours (i've marked one out):

 

A..............B

 

|X............|X

|X............|X

|X............X|

X|............X|

 

 

note that, whilst containing exactly the same alleles, the two genomes are NOT actually identicle.

 

Now, say the offspring recieves the following gamete:

 

X

|

|--recombination inherited

X--from twin A.

 

It's pretty clear, from the lower recombination point, that this is twin A's child (the upper recombination point is a new one, not inhereted from either parent). Of cource, it could just be a coincidence, but the whole thing could be approached probabalistically, eg:

 

 

if the child has recombinations at point a, b, c, d, w, x, y and z;

 

w, x, y, and z are recombinations not present in either twin, and so can be assumed to be recombination during formation of sperm, reguardless of which twin is the parent;

 

recombination points a, b, c and d are present in twin A, but not twin B;

 

therefore, what is the probability of both twin A and twin B's child having the recombinations at those points? if it's really really low, i'd say youv proven that it's twin A's child.

 

As for how easy that would be to do experimentally...

[Immunologist]

I think Dak got a more simple approach (and probably more verifiable).

 

If a recombination occured in the parents, finding it in the child would allow to trace the parent.

 

If that was a teacher's question, recombination would surely be the answer.

[chuinhen]

but the problem is Both the couples are genetic indentical !?!?

(wife a = wife b , huband a = husband b )

[Dak]

But like i said, even genetically identical twins are not entirely genetically identical. they'd have recombined differently after fertalisation. This wouldn't, i shouldnt imagine, make a difference in how the genes are expressed in the two individuals in the vast majority of cases, but there's still a difference that you can test for.

 

Actually, as recombination tends to change the length of repetitive DNA, if you're really lucky, they might even have slightly different RFLP DNA fingerprints (not sure wether the difference would show up on an RFLP test tho).

[ecoli]

Actually' date=' as recombination tends to change the length of repetitive DNA, if you're really lucky, they might even have slightly different RFLP DNA fingerprints (not sure wether the difference would show up on an RFLP test tho).[/quote']

 

AFAIK, it usually doesn't.