Fig. 1. Timeline of significant discoveries and developments in telomere biology and their clinical relevance.

Since dyskeratosis congenita was first described in the early 1900s, there have been significant developments in the knowledge of telomere biology over the last century. It is now known that telomeres are DNA-protein structures found at the ends of chromosomes and provide stability to chromosomes and prevent deterioration during cellular replication. Telomere length attrition thus leads to cellular senescence and triggers cell death pathways. Telomere biology disorders are a group of monogenic disorders of premature aging arising due to accelerated shortening of telomere lengths. It has a highly variable presentation due to various germline mutations and incomplete penetrance. Clinical phenotypes vary from multisystem disorders presenting in childhood such as dyskeratosis congenita and single organ disorders such as idiopathic pulmonary fibrosis, which may present in late adulthood. Despite the significant advancement, the true extent of the syndrome remains unknown and further genetic mutations have yet to be identified.