Elevated Telomeric Repeat-Containing RNA (TERRA) Levels Linked to Telomere Dysfunction and Telomerase Inactivity in Blood Cells of Children With Aplastic Anemia.

Background Aplastic anemia (AA) is characterized by pancytopenia and hypocellularity of the bone marrow. Certain inherited or genetic forms of AA have also been associated with telomere dysfunction. Here, we report the clinical manifestations of eleven AA patients aged between one and 12 years, along with the expression of a few candidate genes involved in the telomere length (TL) maintenance pathway. Methods The clinical manifestations were recorded for all the patients. The average telomere length of peripheral blood mononuclear cells (PBMC), the expression of telomerase subunits, telomere-associated proteins, and chromosome-specific telomeric repeat-containing RNA (TERRA) in whole blood cells of each patient was compared with an age-matched control group consisting of five clinically confirmed normal individuals. Results Out of 11 AA patients, four were found to have upper limb anomalies, and two showed short stature along with other defects. All the patients showed significantly shorter telomere length compared with the age-matched control group. The essential subunits of telomerase (hTERT and hTERC) were significantly low, and the shelterin protein is abnormally expressed in all patients implicating a compromised TL maintenance pathway. Notably, AA with combined androgen and prednisolone treatment showed a marked reduction of TERRA level than that of AA without androgen/prednisolone therapy. Conclusion Based on the findings and observations made, it appears that there might be an association between telomere dysfunction and elevated levels of TERRA in patients diagnosed with aplastic anemia who are 12 years of age or younger.