Genetics: Codominance: Will these always be?

Question

Will breeding a F1 white chicken with an F1 black chicken always give you a blue chicken or is there a ratio? What if instead of chickens, they were a brown horse and a white horse, will all the offspring be Palomino?

Answer 1

if you talking about codominance yes black + white chicken will give you a Black&white phenotype , which is different from parental organisms. if you cross Black (BB) with white (WW) the offspring's will be 100% (BW) like you said blue chickens, and if you cross those offspring's the ratio will be 1BB -->Black 1WW---> white  and 2 BW --> blue.  Same idea with horses and also look up at ABO blood types is also a good example of codominance

Answer 2

If the alleles are co dominant then yes it will result in a phenotypically black and white chicken. Same as the horse. There are ratios but they apply to dominant and recessive genes, not co dominance. It was Mendell who first discovered the ratios in his experimentation with pea plants. Many genetic condition are associated with the ratios.

eg. Certain people can taste certain chemicals. If two people CAN taste these chemicals but carry the recessive gene also it will result in a ratio.

T=they can taste it

t=they cannot

Tt x Tt = genotype of 1:2:1 (TT:Tt:tt)

              phenotype of 3:1 (taster:non-taster)

Hope this makes sense