Clinical utility of relative telomere length analysis in pediatric bone marrow failure.

Introduction: Telomere length related studies are limited in pediatric marrow failure cases due to difficulty in establishing population specific age related normograms. Moreover, there is paucity of data related to clinical relevance of telomere length in idiopathic aplastic anemia (IAA) and non telomere biology inherited bone marrow failure syndrome (IBMFS) cases.

Methodology: Hence, in current study we investigated Relative telomere length (RTL) by RQ-PCR in 83 samples as: healthy controls (n = 44), IAA (n = 15) and IBMFS (n = 24). In addition, we performed chromosomal breakage studies and targeted NGS to screen for pathogenic variants.

Results & Conclusion: Median RTL was significantly different between control vs. IBMFS (p-0.002), IAA vs. IBMFS (p-0.0075) and DC vs. non-DC IBMFS (p-0.011) but not between control vs. IAA (p-0.46). RTL analysis had clinical utility in differentiating BMF cases as 75 % (9/12) of DC had short/very short telomeres compared to only 17 % (2/12) of non-DC IBMFS, 7 % (1/15) of IAA and 7 % (3/44) of controls (p < 0.001).