DNA question

[Southern_Heart]

I was thinking of DNA and this popped into my mind.

I am really not savy on DNA, but will full brothers have the same DNA or will they be some what different down the line of markers?

Just wondering

Thanks

Joyce

 

[uwharrie]

DNA may be close but will never be the same except in the case of identical twins, and I doubt that happens in horses ( at least where they survive)

 

[HGFarm]

Oh you could open a whole can of worms here...

In humans, the father always passes their same Y chromosomes to the sons. Females from the same father will show the same X chromosomes. Mitochronidial DNA is passed from the mother. Men have this DNA but do not pass it on. If you do a test on a brother and sister to see if they are related, a full test would have to be done and I understand it is only about 80% accurate.

My understanding is that full siblings of course will always share much more DNA than those only half related or less, but full siblings have about 50% of their DNA in common. Half siblings about 25%. This is one way they can determine if kids are full or half brothers, is by how much of their DNA is common to each other.

No one will ever have exact DNA, and it sounds like about 50% at best.