An example often stated for codominance is blood groups, where both alleles version of the protein is expressed and can be found in the cell membrane.
An example of incomplete dominance often given is of red and white flowered snapdragons giving pink flowered offspring because enzymes for both pigments are transcribed and translated and the mixing of these pigments gives the intermediate phenotype.
In both these examples both alleles are transcribed and translated.
In the text-book mendelian situation of a dominant and recessive allele are there actually a cellular mechanisms by which a 'dominant' allele silences the 'recessive' allele and inhibits it's translation, transcription or both? If so are there any well characterised examples?
Or are all alleles actually codominant at the transcription/protein level? e.g like in many recessive gentic diseases where both the mutant and the normal protein are present (cystic fibrosis, sickle cell anemia etc) but the activity of the normal protein gives the 'healthy' phenotype.