Sometimes alleles are INCOMPLETE DOMINANT , example is "blue" on chickens. It always shows, but stronger when purebred. Bl/bl+ = blue, Bl/Bl = splash, bl+/bl+ = wildtype, black on a unicolor chicken.
But we can notice differences in the gradation of the "blue-color" what is called in the hobby "colorazione intermedia" not the color "Blue" itself.
(because one of the genetic-rules say : a Dominant gene (what Blue = Bl/bl+ is) need only 1 allele (one dose = Bl/bl+ = Blue) to show the same phenotype as 2 alleles (two doses = Bl/Bl = Splash) but as we all know is this not correct) !!!
[Modificato da Danny_57 21/08/2011 15:05]