Frillback pigeon genetics
The incredible curled feathers of the Frillback pigeon are, according to research by L. Paul Gibson, controlled by two partially dominant morphological modifier genes, given the symbols “Cu1” and “Cu2“. Evidence suggests that a third gene, perhaps one that causes longer feathers, may also be involved.
Some breeders have concluded that the Grizzling factor present in the Frillback breed may be a different gene to the G//+ found in other pigeons, due to it apparently not creating “stork-marked” birds in the homozygous state G//G. Research, again by Gibson, appears to show that it is in fact G, with a separate (likely recessive) modifier gene inhibiting G//G creating the “stork” phenotype.
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