To explore the effect of aging, a cohort study is being performed on Sado Island, which is located in the Sea of Japan. Sado Island is close to the eastern coast of Japan, yet its population speaks the western Japanese dialect. Consequently, the genetic background of the population of Sado Island is of interest. Based on Nei’s genetic distance, we compared the allele frequencies of people from Sado Island to those of people from Nagahama and Miyagi, which are located in the western and northeastern parts of Honshu, respectively. The results showed that the populations of Miyagi and Nagahama are genetically closer to each other than to the population of Sado Island. Because the Sado and Honshu Islands are isolated by a channel, it is possible that genetic drift occurred within Sado Island, which would explain the uniqueness of the people of this region.

为了探索衰老的影响，正在日本海的佐渡岛进行一项队列研究。佐渡岛靠近日本的东海岸，但其人口却说日本西部方言。因此，佐渡岛人口的遗传背景引起人们的兴趣。根据Nei的遗传距离，我们比较了佐渡岛人与长滨和宫城人的等位基因频率，它们分别位于本州的西部和东北部。结果表明，宫城和长滨的种群在遗传上比佐渡岛的种群更接近。由于佐渡岛和本州群岛之间是通过渠道隔离的，因此佐渡岛内部可能发生了遗传漂移，