What Is the Founder Effect? — Definition & Examples

The island population will always have the exact same gene frequency as the mainland, so the disease will be rare.

The group that left for the island could have no carriers, so no one on the island would ever get the disease.

The group that left for the island might have one or a few carriers of the gene, so the disease could become much more common on the island.

The group that left for the island will always have a carrier, so the disease will kill any children on the island.