Self Assessment Answer # 6
for Lesson 5

by Dr Jamie Love Creative Commons Licence 2002 - 2005


You are 50% (half) identical to your brothers and sisters. That may not have been too obvious and you'd have to think about it in terms of statistics but maybe we can explain it here with what you already know.

You are half identical to your father and half identical to your mother. [Right?] So are your brothers and sisters, but the half they received from each parent is not the same half you received! And it isn't the "other half" either!

Remember, meiosis I makes sure that gametes are very different. The genetic material you received from your father's sperm is not the same genetic materials your brother or sister received. The same goes for the genetic materials inherited from mom's egg.

Indeed, the odds are that the sperm materials you inherited are only 50% identical to the sperm materials your brother or sister received. The same is true for the genetic materials from mom. That means you share with your brother or sister ¼ of dad's genes and ¼ of mom's genes. That's a total of ½ shared but the remaining ½ of your genetic material is not shared!


Return to the Question.