WHY SIBLINGS DON’T INHERIT THE SAME DNA

SIBLINGS, other than identical twins, are only 50 per cent similar genetically, which means that they are also 50 per cent different.

The basic reason is that our DNA comes in pairs, called chromosomes.

For each of the 23 pairs of chromosomes, we inherit one from our mother, the other from our father. So siblings have a 50- 50 chance of inheriting the same chromosome from their mother or their father. However, the chances that siblings inherit exactly the same chromosomes from their mother and father for all 23 pairs is vanishingly small.