The 75th In Silico Megabank Research Seminar will be held on Friday, September 2.
This Time, we will be welcoming Dr. Makoto Shimada, Fujita Health University as our lecturer, and he will be speaking on “Explore the relationship between triplet repeat disease and human revolution through selective pressure for human STR sequence ”.
・Date/Time: September 2 (Friday) 5:00 pm‐6:30 pm
・Venue: Small Conference Room 2(3rd Floor), Tohoku Medical Megabank Building
・Title: Explore the relationship between triplet repeat disease and human revolution through selective pressure for human STR sequence
・Lecturer: Dr. Makoto Shimada (Institute for Comprehensive Medical Science, Fujita Health University)
*This lecture is transferable as a class in the medical research-related lecture course.
・Abstract: In STR (Short Tandem Repeat), repeating sequences of very short base segments, the number of tandem repeats changes very frequently. Thus, there has been a hypothesis that adaptive trait and evolutionary stable state were quickly established using the high variability of the number of tandem repeat. On the contrary, human STR sequence is known to have multiple repetitive sequences which are the cause of neurodegenerative diseases. However, why such dangerous repetitive sequences are maintained among human population is not yet known well. We have identified the number of the STR repetition and repeat polymorphism within human genome by integrating information of polymorphism into H-invDB, the genetic database that we developed and released to the public. Furthermore, we evaluated the selective pressure for each STR through intercomparison. The result showed that repetitive amino-acid sequences were formed in STR in amino acid coding regions due to 2 mechanisms each of which are represented by proline repeats and glutamine repeats while keeping the repeats short at the DNA sequencing level. Moreover, it was revealed that glutamine repeats have a tendency to have longer repeats at amino-acid level and that especially the repeat polymorphism exists in the genes related to the regulation of the generation of nervous system and brain. These results suggest the possibility that polymorphism of these repeats facilitated the diversification of the functions related to the regulation of the generation of nervous system and brain. In our article, we have further argued the relationship between the evolution of sociality throughout human evolution and the switch function for the regulation of STR neural development.
・Organizer: Yosuke Kawai, Kazuharu Misawa, Masao Nagasaki