Of all the Polynesian populations compared in a new genome study, the people most closely related to Native Hawaiians are the Rapa Nui of Easter Island, roughly 4,400 miles away on the opposite edge of the Pacific. The study, published Oct. 8 in Science, suggests the founders of both islands came from the same ancestral group of long-distance voyagers, with deeper roots traced to Mangareva in French Polynesia.

The research analyzed genomic data from 1,050 people across Polynesian populations and incorporated data from Rapa Nui, Native Hawaiians, Samoa and Tonga, according to the University of Chile, whose professor Mauricio Moraga is a co-author. Keolu Fox, an associate professor of anthropology at the University of California San Diego, is one of the study's senior authors. The paper made the cover of that week's issue.

The finding matters for two reasons — it refines a familiar settlement story that placed the Marquesas at the center of Hawaii's origins, and it shows how the same small founding crews left a medical legacy. Rare disease variants became common in some island populations, yet they are missing from the global databases doctors rely on to decide which conditions to screen for.

Two Remote Islands, One Founding Lineage

Hawaii and Rapa Nui are each more than 1,800 miles from the nearest inhabited Polynesian island, Fox explained in a published Q&A with Honolulu Civil Beat columnist Olin Lagon, who describes Fox as a friend. Hawaii is the only Polynesian population north of the equator, while Rapa Nui sits in the cold South Pacific.

The team tested the link four ways, including gene frequencies, the amount and length of DNA segments shared between islands, and 2,500 family trees built by resampling the data. Hawaii and Rapa Nui paired off by themselves in 61% of those trees, Fox said. Mangareva took that position about 10% of the time and the Marquesas less than 3%.

The authors call the ancestral voyagers Holomoana Nui, which the study translates as great ocean voyaging. Their results support the Marquesas as a dispersal hub for remote Polynesia, but point to a founding path to Hawaii that passed through Mangareva. The work builds on a 2021 study that proposed Rapa Nui was settled around the year 1200 through an expansion linked to Mangareva.

Tracing Voyages Through Shared DNA

Shared stretches of DNA get shorter with each generation, which lets researchers estimate population sizes back through time. Using 581 genomes from Tahiti, the team estimated that the founding population behaved like roughly 800 people per generation about 34 generations ago, which works out to around the year 1069 at 28 years per generation.

That estimate falls inside the range of 1025 to 1120 that archaeologists had already derived from radiocarbon dating for settlement of the Society Islands. The genetic record then shows rapid growth for about 700 years, followed by a drop of nearly 40% nine to 10 generations ago, which the researchers link to disease after European contact in the 1700s.

The genetic results line up with other lines of evidence. A 1966 tree of Polynesian languages grouped Hawaii, Mangareva and the Marquesas, and DNA from Pacific rats that voyagers carried on their canoes also links Hawaii with the Marquesas.

A Medical Blind Spot in Global Gene Databases

Each new island was founded by a few dozen people, so rare genetic variants could become common by chance. When that process repeats across a chain of islands, the effects stack. The team reported that remote Eastern Polynesia shows some of the strongest founder signals it has measured, far stronger than in Finland, a population often studied for founder effects.

In French Polynesia, where more than 1,000 genomes allowed representative sampling, the researchers reported three recessive disease variants at high carrier frequencies. About 1 in 40 people carries an ADAMTSL4 variant tied to early lens dislocation in the eye, about 1 in 27 carries a PDE6B variant tied to retinal degeneration, and about 1 in 45 carries a FAN1 variant tied to a rare kidney disease that can lead to kidney failure. Being a carrier does not cause disease; a child must inherit two copies.

The American College of Medical Genetics and Genomics uses a carrier rate of 1 in 200 as a threshold for recommending screening, Fox said. The problem is that gnomAD, a reference database of more than 800,000 genomes and exomes, has no Polynesian population group, so conditions common only in Polynesia cannot reach that bar.

Caveats the Researchers Spell Out

The genome cannot say which island settled which, or reconstruct individual voyages. Moraga told the University of Chile that the genetic connection supports a shared origin but does not show that the same individuals reached both islands. He also cautioned that clinical frequencies from French Polynesia cannot be applied automatically to Rapa Nui.

The same limit applies to Hawaii — the team did not report disease frequencies for Native Hawaiians. Its Native Hawaiian data came from the federal All of Us research program, which Fox said had too few Hawaii participants and substantial recent non-Polynesian ancestry in the samples. "I would rather report nothing than report something wrong," he said.

Hawaii Data Still Missing

Fox said the team hopes to build a dataset of 1,000 or more Native Hawaiian participants, governed by Indigenous data sovereignty rules and stored on servers in Hawaii, with recruitment spread across traditional land divisions on each island. He said the researchers had reservations about the consent process used for the All of Us data.

For now, the findings do not change medical guidance for individuals. Native Hawaiian and other Pacific Islander families dealing with unexplained kidney failure or early vision loss can ask their doctors whether a referral to a genetic counselor makes sense, but no Polynesian-specific screening panel exists yet.

The bottom line is that DNA from living people points to a shared founding population for two of the most remote places humans ever settled. The next step, researchers say, is gathering enough Hawaii-based data, on terms set by the community, to turn that history into better care.

What Readers Want to Know

What did the Science study find?

Among the Polynesian populations compared, Native Hawaiians are most closely related to the Rapa Nui of Easter Island. The authors suggest both islands were founded by the same ancestral voyaging population with roots in Mangareva.

How far apart are Hawaii and Rapa Nui?

The islands sit roughly 4,400 miles apart, and each is more than 1,800 miles from the nearest inhabited Polynesian island, according to study co-author Keolu Fox.

Does this mean the same canoe crew settled both islands?

Not necessarily. Researchers say the genetic link supports a shared ancestral population but cannot reconstruct specific voyages or show that the same individuals reached both islands.

When was Tahiti settled, according to the DNA?

The team estimated a founding bottleneck about 34 generations ago, around the year 1069, which matches archaeological dates of 1025 to 1120 for the Society Islands.

What do the findings mean for health?

In French Polynesia, three recessive disease variants affecting the eyes and kidneys are carried by roughly 1 in 27 to 1 in 45 people. Those results cannot be applied directly to Hawaii or Rapa Nui.

Are Native Hawaiian disease rates known from this study?

No. The researchers said they lacked enough Native Hawaiian data to report reliable frequencies and hope to build a larger, community-governed dataset.