Grutzner, Frank, Rens, Willem, Tsend-Ayush, Enkhjargal, El-Mogharbel, Nisrine, O'Brien, Patricia C. M., Jones, Russell C., Ferguson-Smith, Malcolm A., Marshall Graves, Jennifer A.. Nature Publishing Group; 2004. In the platypus a meiotic chain of ten sex chromosomes shares genes with the bird Z and mammal X chromosomes.