AN UNUSUAL SEX CHROMOSOME CONSTITUTION FOUND IN THE AMAMI SPINOUS COUNTRY-RAT, TOKUDAIA OSIMENSIS OSIMENSIS
- 1 January 1977
- journal article
- research article
- Published by Genetics Society of Japan in The Japanese Journal of Genetics
- Vol. 52 (3) , 247-249
- https://doi.org/10.1266/jjg.52.247
Abstract
The diploid chromosome number of the Amami spinous country-rat, T. osimensis osimensis, was found to be 25 in both sexes, lacking an X in the female and a visible Y in the male. Twelve bivalents and 1 univalent were shown in the 1st meiotic metaphases of the male germ cells. Bone marrow cells obtained from the long bones of the limbs and germ cells of the testes were used for the cytogenetical analyses. The diploid chromosome number of the spinous country-rat was 25 in both sexes and the complement showed 11 pairs of metacentrics and submetacentrics, 1 pair of acrocentrics, and 1 unpaired medium-sized submetacentric which was closely similar in both sexes. The spinous country-rat might provide suitable materials to clarify the origin of the unpaired chromosome and the sex-determining mechanism in the animals with the same type of sex chromosome constitution.This publication has 1 reference indexed in Scilit:
- The Chromosomes of the Field Mouse Akodon azarae (Cricetidae, Rodentia) with Special Reference to Sex Chromosome AnomaliesCytogenetic and Genome Research, 1967