Evaluation of genetic introgression from domesticated pigs into the Ryukyu wild boar population on Iriomote Island in Japan

A study on Iriomote Island, part of Japan's Ryukyu Archipelago, reveals significant genetic introgression from domesticated pigs into the Ryukyu wild boar (RWB) population. Analysis of 130 RWB samples using mitochondrial DNA and microsatellite markers identified six distinct haplotypes, with 14% of the population showing European domestic pig lineage traits, particularly in the Panari Islands region. The research also found low genetic diversity and high inbreeding in the Iriomote Main Island (IMI) population, along with substantial genetic distance from Asian domesticated pigs like Meishan. Structure analysis further indicated admixture between RWBs and domestic pigs, suggesting gene flow. These findings highlight the impact of human activities on wild boar genetics and underscore the need for conservation efforts to preserve the unique genetic makeup of these populations.

Murakami, K., Yoshikawa, S., Konishi, S., Ueno, Y., Watanabe, S., & Mizoguchi, Y. (2014). Evaluation of genetic introgression from domesticated pigs into the Ryukyu wild boar population on Iriomote Island in Japan. Animal Genetics, 45(4), 517–523. https://doi.org/10.1111/age.12157