These were Levi’s sons by name: Gershon, Kohath, and Merari.

Kohath’s sons by their clans were Amram, Izhar, Hebron, and Uzziel.

The Amramite clan, the Izharite clan, the Hebronite clan, and the Uzzielite clan came from Kohath; these were the Kohathites.

Now Korah son of Izhar, son of Kohath, son of Levi, with Dathan and Abiram, sons of Eliab, and On son of Peleth, sons of Reuben, took

These were the Levites registered by their clans:
the Gershonite clan from Gershon;
the Kohathite clan from Kohath;
the Merarite clan from Merari.

These were the Levite family groups:
the Libnite clan,
the Hebronite clan,
the Mahlite clan,
the Mushite clan,
and the Korahite clan.

Kohath was the ancestor of Amram.