Ornithorthynchus anatinus (Platypus, X1-5Y1-5): Grutzner et al. (2004)
Ornithorthynchus anatinus (Platypus)
meiotic chromosomes
male X1Y1X2Y2X3Y3X4Y4X5Y5
female X1X1X2X2X3X3X4X4X5X5
https://gyazo.com/0e0b5d15821e40ec4b7b1fee332ce4f8
Figure3
The authors observed and described sex chromosomes in the platypus. However, the platypus has X1-X5 and Y1-Y5 chromosomes in male , so sex chromosomes need to form the multivalent chain at male meiosis to separate accurately.
After making the multivalent chain among X1-X5 and Y1-Y5, chromosomes have to be separeted into two daughter cells at MI accurately. However, X1-X5 and Y1-Y5 must be separated into distinct cells. How do the cell control such chromosome separation? Can mictrotuble dinstinguish pairs of X1-X5 from pairs of Y1-Y5?