User blog comment:Jabberwokk/Genealogy of the Gods/@comment-3146930-20110405223305

it is possible that the powers themselves come from the god gene, but some physical features can change between the parent and god parent. For example, the children of Hermes all look different except for the fact they have pointy ears. All of Athena's kids are blond even if athena has black hair, but that could be a result of a mutated gene or that athena only likes blond guys. Jason and Thalia have different colored hair, but have the same electric eyes, most likely a gene that Zeus passed down