Why are people in Oceania overweight? -Origin of the obesity-related alleles-

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K17651
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Physical anthropology; Human genetics
• Research Institution: The University of Tokyo
• Principal Investigator: NAKA IZUMI 東京大学, 大学院理学系研究科(理学部), 特任研究員 (10723778)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: オセアニア / SNP / BMI

Outline of Final Research Achievements

Why are Oceanians overweight? To answer this question, we analyzed SNPs reported to be associated with increased BMI in Australian Aborigines and East Asians. Although two SNPs, rs1347857 and rs11671664, were significantly associated with increased BMI in the Oceanian populations, their effects on the population mean (2βf) of BMI was small, and the BMI-associated alleles inherited from the ancestral population alone failed to explain higher BMI in the Oceanian populations. A polymorphism on the GIPR gene is known to be strongly associated with glucose levels at 2 hours after oral glucose tolerance test. Our sequence analysis detected five novel polymorphisms at the RBP binding site on the GIPR gene in Tongan subjects.

Free Research Field

人類遺伝学

Academic Significance and Societal Importance of the Research Achievements

オセアニア地域において、肥満や肥満からもたらされる高血圧、糖尿病や脂質異常症などの生活習慣病は深刻な健康問題となっている。本研究によって、祖先集団から受け継いだBMI増加関連アリルの蓄積のみではオセアニア集団の肥満罹患率の高さを説明することはできなかった。
オセアニア集団特異的変異の存在が明らかになり、リモートオセアニアに移住した人類が、新たな環境に適応する過程で生じた遺伝的多様性の理解にはさらなる解析が必要である。