1. Chromosome Dynamics Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO); Madrid Spain
2. Telomeres and Telomerase Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO); Madrid Spain
3. Department of Cell Biology, Albert Einstein College of Medicine; Bronx NY USA
4. Comparative Pathology Unit, Biotechnology Programme, Spanish National Cancer Research Centre (CNIO); Madrid Spain