RRSS is the phenotype of a heterozygous fly.
When two identical genes are present, a homozygous phenotype results.
When an organism is heterozygous, it has two distinct alleles of the same gene. For instance, pea plants can have either homozygous dominant (red-red) or heterozygous red blooms (red-white). They are homozygous recessive if they have white blooms (white-white). Always have heterozygous carriers
The term "heterozygous" describes the presence of several alleles for a given trait. You have a heterozygous genotype for that gene if the two versions differ from one another.
A heterozygous dominant genotype for a trait would be "Tt" if "T" stands for the dominant allele of a trait (for example, the phenotype of brown fur) and "t" stands for the recessive allele of a trait (for example, the phenotype of white fur).
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