Which traits are codominant or incompletey dominant? (these traits don't have a clear dominant or recessive, the heterozygous condition shows a "blending or a "middle" condition)

Codominant - traits don't have a clear dominant or recessive,

incomplete dominance-the heterozygous condition shows a "blending or a "middle" condition

Explanation:

Some alleles bring about intermediate expression in the phenotype. Such alleles are called codominant alleles since they express themselves equally in the phenotype. In the heterozygous state, the offspring does not resemble either of the parents. An example is the ABO blood group alleles. Alleles A and B are codominant each being expressed equally.

Incomplete dominance, one allele expresses itself more strongly than the other. An example is sickle cell anaemia. Heterozygotes who carry the sickle cell gene are said to have a condition called sickle cell trait. The heterozygous allele has a stronger influence on the phenotype than the dominant allele state.