Changes in gene expression resulting from epigenetic and/or genetic changes play an important role in the evolutionary divergence of phenotypes. To explore how epigenetic and genetic changes are linked during primate evolution, we have compared the genome-wide DNA methylation profiles (methylomes) of humans and chimpanzees, which have a 1.2% DNA sequence divergence, of sperm, the frontal cortices, B cells, and neutrophils. We revealed that species-specific differentially methylated regions (S-DMRs), ranging from several hundred base pairs (bp) to several kilo base pairs (kb), were frequently associated with sequence changes in transcription factor-binding sites and insertions of Alu and SVA retrotransposons. We then generated a reference macaque sperm methylome map and revealed, in sperm, that both human and chimpanzee S-DMRs arose more frequently owing to methylation loss rather than gain. Moreover, we observed that the sperm methylomes contained many more hypomethylated domains (HMDs), ranging from 20 to 500 kb, than did the somatic methylomes. Interestingly, the sperm HMDs changed rapidly during primate evolution; hundreds of sperm HMDs were specific to humans, whereas most somatic HMDs were highly conserved between humans and chimpanzees. Notably, these human-specific sperm HMDs frequently occurred in regions exhibiting copy number variations. Our findings indicate that primate evolution, particularly in the germline, is significantly impacted by reciprocal changes in the genome and epigenome.

Semen collection by urethral catheterization and electro-ejaculation with different voltages, and the effect of holding temperature and cooling rate before cryopreservation on semen quality in the Japanese macaque (Macaca fuscata

The research is one of the most important roles for zoo, however, the budget, staffs and instruments for research are not enough. So collaboration with other research institutes is effective. In this article, I introduce the distinction of research in Sapporo Maruyama Zoo and discuss about the research system of zoo. Sperm collection from endangered species is one of the research themes of our zoo. Collaborating with Hokkaido University, I succeeded in collecting the sperm of the snow leopard, polar bear and spotted hyena with urethral catheterization, which is a new method of sperm collection. I also tried artificial insemination in the Amur tiger applying the new method. This study is important for conservation of wildlife and will be progressed effectively with the cooperation of the university. Investigation of wild bats in Sapporo city is another research theme of our zoo. This research is conducted with the team of wildlife researchers, and ordinary people can join the research activities. This research contributes to not only revelation of the ecology of wild bats but also the environmental education for citizens of Sapporo. These researches related to the conservation and education proceeded with some collaborators are ideal styles of the research of zoo. It is thought that such characteristic research contributes to increasing the value of zoo.