The ancestor of extant Japanese fancy mice contributed to the mosaic genomes of classical inbred strains
- Toyoyuki Takada1,
- Toshinobu Ebata1,
- Hideki Noguchi1,
- Thomas Keane2,
- David Adams2,
- Takanori Narita1,
- Tadasu Shin-I1,
- Hironori Fujisawa3,
- Atsushi Toyoda1,
- Kuniya Abe4,
- Yuichi Obata4,
- Yoshiyuki Sakaki5,
- Kazuo Moriwaki4,
- Asao Fujiyama1,
- Yuji Kohara1 and
- Toshihiko Shiroishi1,6
- 1 National Institute of Genetics;
- 2 Wellcome Trust Sanger Institute;
- 3 The Institute of Statistical Mathematics;
- 4 RIKEN BioResource Center;
- 5 RIKEN Genome Science Center
- ↵* Corresponding author; email: tshirois{at}lab.nig.ac.jp
Abstract
Commonly used classical inbred mouse strains have mosaic genomes with sequences from different subspecific origins. Their genomes are derived predominantly from the Western European subspecies Mus musculus domesticus, with the remaining sequences derived mostly from the Japanese subspecies M. m. molossinus. However, it remains unknown how this intersubspecific genome introgression occurred during the establishment of classical inbred strains. In this study, we resequenced the genomes of M. m. molossinus -derived two inbred strains, MSM/Ms and JF1/Ms. MSM/Ms originated from Japanese wild mice, and ancestry of JF1/Ms was originally found in Europe and then transferred to Japan. We compared the characteristics of these sequences to those of the C57BL/6J reference sequence and the recent datasets from the resequencing of 17 inbred strains in the Mouse Genome Project (MGP), and the results unequivocally show that genome introgression from M. m. molossinus into M. m. domesticus provided the primary framework for the mosaic genomes of classical inbred strains. Furthermore, the genomes of C57BL/6J and other classical inbred strains have long consecutive segments with extremely high similarity (>99.998%) to the JF1/Ms strain. In the early 20th century, Japanese waltzing mice with a morphological phenotype resembling that of JF1/Ms mice were often crossed with European fancy mice for early studies of "Mendelism" which suggests that that the ancestor of the extant JF1/Ms strain provided the origin of the M. m. molossinus genome in classical inbred strains and largely contributed to its intersubspecific genome diversity.
- Received February 18, 2013.
- Accepted April 10, 2013.
- © 2013, Published by Cold Spring Harbor Laboratory Press
This manuscript is Open Access.
This article, published in Genome Research, is available under a Creative Commons License (Attribution-NonCommercial 3.0 Unported), as described at http://creativecommons.org/licenses/by-nc/3.0/.
