The polymorphism of telomerase RNA component gene in patients with systemic sclerosis

The molecular basis of senescence and immortalization is not still understood, but one hypothesis for which there has recently been much evidence involves the shortening of telomeres. It can be hypothesized that abnormalities of telomerase contribute to the emergence of abnormal fibroblast clones in systemic sclerosis (SSc).

To study possible telomere abnormalities with respect to polymorphism of the telomerase RNA component gene.

Fifty-three patients with SSc and 98 normal controls were studied. Polymerase chain reaction was used to amplify 598 bp of the telomerase RNA component gene. Amplified fragments were digested with restriction enzyme BsrDI.

The frequency of the A allele in SSc (41.5%) showed no significant difference from that in the normal controls (32.1%). The frequency of the A/A alleles in SSc (18.9%) was significantly higher than in normal controls (5.1%), compared with G/G (35.8% and 40.8%, respectively; P < 0.02), G/A (45.3% and 54.1%, respectively; P < 0.01) and G/G plus G/A (81.1% and 94.9%, respectively; P < 0.01).

These results showed the possible involvement of a telomerase abnormality in the emergence of abnormal fibroblast clones in SSc skin-derived fibroblasts.