classic genetics question (Gustavo A. Seluja)

Graham Dellaire dellaire at odyssee.net
Sun Jul 13 22:29:17 EST 1997


Okay I will bite!

TWO BROTHERS are more genetically similar.

Here is my reasoning.

Lets say the whole compliment of genes from Mother or Father is half
each of their respective parents (P1F P2F and P1M and P2M for
mother...etc)  so:

Father is 50% P1F and 50% P2F and Mother is then similar with 1/2 P1M
and 1/2 P2M

So the F1 of their cross (which are the brothers in question) are 1/4
P1F, 1/4 P2F, 1/4 P1M and 1/4 P2M on average (remember treating the
haploid compliment of each parent as a whole).

The brothers are identical in this respect, where as the father does not
have P1M or P2M alleles (unless this is consanguinous then that is a
whole new ball game...<smile>).

So the two brothers are more alike genetically.


Graham








More information about the Genstruc mailing list