A new database provides information on the frequency of genetic variations within 3552 Japanese individuals, and facilitates comparisons with other populations. The reference panel, constructed by Kengo Kinoshita of Tohoku University, Sendai, and colleagues in Japan is also the first large-scale database to provide genetic variation frequency information on the X chromosome and mitochondrial DNA in the Japanese population. The methods used to sequence the genetic data are similar to those used in other large databases, allowing comparisons with other populations. The population size and methods used to compile the database overcome limitations in previous Japanese reference panels. This and similar databases that catalog genetic variations within populations can improve efforts towards personalizing healthcare and contribute to the study of human population genetics. The database is publicly available online.
Article Collection- Genome projects and researches in Japan
Researchers in Japan have assembled a Japanese reference genome, which includes sequences missing from the international reference genome, as well as others specific to East Asian populations. A team led by Masao Nagasaki and Masayuki Yamamoto sequenced a Japanese individual using a method, which produces longer sequences than previous technologies. Using this approach, they identified thousands of sequences spanning 2.5 million bases, which were absent in the international reference genome. Many of these were sequences able to move within the genome. They showed that the majority of these sequences are also present in early humans and chimpanzees, demonstrating that their absence from the current reference is due to deletions or limitations of earlier sequencing methodologies. In addition to providing a population-specific reference, these findings demonstrate the importance of continually improving the international reference genome.