One disease affecting these structures is X-chromosome linked to mutations in the DKC1 gene and may require bone marrow transplants. Dyskerin helps to stabilize a catalytic complex that acts on this structure. Deficiencies in maintaining these structures, which are measured by the Q-FISH technique, are (10[1])a major risk factor (10[1])for idiopathic pulmonary fibrosis. Cajal bodies may serve to recruit RNA structures that act on these structures. The Hayflick limit is based on the (10[1])length of these structures (10[1])that can be extended by TERT. Shortened examples of these structures that lose their shelterin cap can trigger senescence, and these structures consist of repeating TTAGGG motifs. For 10 points, what DNA sequences protect the ends of chromosomes? ■END■