Just wondering if two step-siblings had a baby how much DNA of the original shared parent (grand parent of baby) would the baby receive? 50% or more or less, or doesn't it work like that? Obviously it's going to be too much DNA but I'm just wondering lol.
DNA shared between step-siblings, how much would go into baby?
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Yeah, you mean half siblings OP.
Either way, don't be putting your junk in your sister. Just wrong dude!
WAT?
Assuming that the OP does mean half-siblings and not step-siblings, would the correct answer be "between 0 and 100%, depending on which genes the egg and sperm had"?
I'm thinking it's like this:
Call the common parent A and the two half-siblings B and C. B's other parent is D, C's other parent is E.
B has half their genes from A and half from D.
C has half their genes from A and half from E.
Each of B's gametes could contain only genes from A, only genes from D or any mix in between.
Each of C's gametes could contain only genes from A, only genes from E or any mix in between.
So a baby from B and C could contain no genes from A at all (all D from B, all E from C), genes only from A or any mix of genes from A, D and E.
It's not a good idea, though. There's too much chance of too little diversity, unless you're using screening and in vitro fertilisation.
I'm thinking it's like this:
Call the common parent A and the two half-siblings B and C. B's other parent is D, C's other parent is E.
B has half their genes from A and half from D.
C has half their genes from A and half from E.
Each of B's gametes could contain only genes from A, only genes from D or any mix in between.
Each of C's gametes could contain only genes from A, only genes from E or any mix in between.
So a baby from B and C could contain no genes from A at all (all D from B, all E from C), genes only from A or any mix of genes from A, D and E.
It's not a good idea, though. There's too much chance of too little diversity, unless you're using screening and in vitro fertilisation.
You'd expect 12.5% shared genetic material on average in the child of two half-siblings.
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most of the stuff floating around about mass deformities are myths tbh, there is a slightly raised chance of disorders appearing in 100% sibling or parent-child inbreeding but if you've watched too many hills have eyes films you are misled about it ^^
About your half-sister?
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It's not so much about what it 'is', but where it's from. Two half-siblings could both trace half their DNA back to a single parent. Their offspring would be able to trace half of it's DNA back to one parent and half to the other. But there's nothing to say that it has to have initially come from the shared parent.
There are three main sources of genetic variation. Mutation, Independent Assortment and Crossing Over. The last two are mainly responsible for the gametes having a random selection of parent the parent DNA.
And no, it is not a 'myth' that closely related individuals will produce offspring at a much greater risk of developing genetic conditions, such as deformities, a lack of immunity or some such.
There are three main sources of genetic variation. Mutation, Independent Assortment and Crossing Over. The last two are mainly responsible for the gametes having a random selection of parent the parent DNA.
And no, it is not a 'myth' that closely related individuals will produce offspring at a much greater risk of developing genetic conditions, such as deformities, a lack of immunity or some such.