Non-random chromosome distribution in radial metaphases from the Chinese hamster

Chromosome distribution was analyzed in uncultured radial metaphase cells (corneal epithelium, testicular mitotic cells, cells in diakinesis, and cells in metaphase II) from the Chinese hamster. The hypothesis of random distribution was rejected at the 0.001 level (x ₃ ² = 31.6). — Homologous association was observed for two pairs of chromosomes (3 and 10) in corneal epithelial cells. It was observed for all chromosomes in the testicular mitotic cells. Acrocentric association was observed in all four cell types. The chromosomes associated in four groups of similarly sized and shaped chromosomes. While group membership did not appear to vary, position within the group was highly variable. — An elevenpoint model of chromosome relationships was constructed from the data.