Three ancient individuals from Le Déhus have yielded genome results dated to 4241–3968 BCE. Two male individuals carried Y‑DNA haplogroup I, a lineage observed in both Mesolithic hunter‑gatherers and some later European populations. Mitochondrial haplogroups recorded among the three samples are K, J, and X — maternal lineages that appear in Neolithic and pre‑Neolithic contexts across Europe.
Taken together, these genetic signals are compatible with mixed ancestry scenarios documented elsewhere in northwest Europe: incoming early farmers from Anatolian‑derived groups interacting and admixing with local hunter‑gatherer populations. However, with only three samples, any inference about population structure, admixture proportions, or sex‑biased migration remains highly tentative. The presence of haplogroup I in two males might hint at continuity of local paternal lines or recruitment from groups carrying this lineage, but small sample size prevents robust demographic conclusions.
Genetic data complements the archaeological picture of maritime connections: the mtDNA diversity (K, J, X) suggests links to broader Neolithic networks, while Y‑DNA I underscores the persistence or reintroduction of hunter‑gatherer–associated paternal markers. Future sampling across more burials and settlements on the islands and nearby coasts will be essential to test these preliminary patterns.