noun
dominant gene
A gene that expresses its trait even when only one copy is present. Contrasts with 劣性遺伝子 (recessive gene).
See also: 劣性遺伝子
茶色の目の遺伝子は優性遺伝子です。
The gene for brown eyes is a dominant gene.
優性遺伝子と劣性遺伝子の組み合わせで形質が決まる。
Traits are determined by the combination of dominant and recessive genes.
劣性遺伝子 is a recessive gene, which expresses its trait only when two copies are present, unlike 優性遺伝子 which expresses with just one copy.
Compound of 優性 (dominance) and 遺伝子 (gene). The term is a direct translation of the English 'dominant gene'.