Solving the mystery of centromere evolution

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H03207
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 43050:Genome biology-related
• Research Institution: The Graduate University for Advanced Studies
• Principal Investigator: Innan Hideki 総合研究大学院大学, 統合進化科学研究センター, 教授 (90444140)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: centromere / evolution / population genetics / theory

Outline of Final Research Achievements

We analyzed polymorphism in the human centromeric regions. The data were obtained from public database. Each centromeric region contains highly repetitive region of 171bp of alpha-satellites, flanked by pericentromeric regions where a number of old alpha-satellites locate. We found that the human population has a marked amount of DNA variation in the centromeric regions, including copy number variation and DNA sequence variation within alpha-satellites. An obvious trend is that alpha-satellites that locate more closely are more similar to each other. Our theoretical analysis demonstrated crucial roles of two important mechanisms, one is gene conversion and unequal crossing over that homogenize genetic variation between alpha-satellites and selection to maintain functional (sequence) uniformity of alpha-satellites on the same chromosome.

Free Research Field

集団遺伝学

Academic Significance and Societal Importance of the Research Achievements

セントロメアは細胞分裂における最も重要な機能のひとつであるが、その進化には謎が多い。重要な機能は基本的には制約が強く進化のスピードが遅いのであるが、セントロメアは例外的に早い進化をしている。なぜセントロメアが例外的な進化をしているかを理論的に解析した。分子生物学でもよく研究対象とされるセントロメアに対して、進化的視点からの理解を加えることは、学問の進展繋がると考える。