Optimization of telomere measurement of pig cells by quantitative real-time PCR analysis (qPCR). (A) Telomere primers for pig telomere amplification and 36B4 primers. Telomere primers for human and mouse telomere measurement by qPCR were described previously [23, 24]. (B) Melting curve charts of human telomere primers and mouse telomere primers for pig telomere analysis, respectively. (C) Standard curves for pig telomere amplification, using human telomere primers and porcine 36B4, mouse telomere primers and porcine 36B4, respectively. Telomeres and 36B4 for standard curves were derived by serial dilution of a known quantity of genomic DNA isolated from spleen cells. hTel, primers for human telomere sequence amplification; mTel, primers for mouse telomere sequence amplification; E, amplification efficiency; CT, threshold cycle. Solid circle, telomeres; Hollow circle, 36B4 control.