These differences are not genetically programmed. They are specific to the culture. Suppose the Japanese child and the Swiss child were switched at birth, with the Swiss child raised in Kyoto and the Japanese child raised in Appenzell. The experience of adoptive parents teaches us that the Japanese child will speak Schwyzertüütsch (Swiss German) as flawlessly, and will master that culture with the same ease, as any other child raised in Appenzell; likewise, the Swiss child raised in Kyoto will speak Japanese as well, and be as culturally proficient, as any child born and raised in Kyoto.
