Comparison of the genome sequences between sexes in the Amami spiny rat, Tokudaia osimensis

The Amami spiny rat, Tokudaia osimensis, has very unique sex chromosomes and sex-determining mechanism. The sex chromosome constitution of this species is XO/XO, which is caused by the absence of the Y chromosome. This species also lacks the SRY gene which is sex-determining gene in eutherian mammals. Therefore, it is hypothesized that T. osimensis acquires a new sex-determining gene superseded SRY. Furthermore, T. osimensis is an endangered species and has been protected by the Japanese government as such since 1972. Therefore, we compared male and female genome sequences for two aims: use the information for study of sex-determining mechanism and evolution of the Y chromosome, reserve the information as important resources.