The reaction mixture consisted of 1 ll cDNA, 0.5 mM of each primer (P53 and GAPDH as internal control), iQ SYBR GREEN PERMIX (BIO-RAD 170–880, USA) in a total volume of 20 ll. PCR amplification and analysis were achieved using BIO-RAD iCycler thermal cycler and the MyiQ realtime PCR detection system. All templates were amplified using the following Light Cycler protocol. The primer for P53 was based on the sequence published in gene bank FJ233106.1 for O. niloticus; forward primer; GCATGTGGCTGATGTTGTTC and the reverse one GCAGGATGGTGGTCATCTCT. The fast start polymerase was activated and
cDNA denatured by a pre-incubation for 10 min at 95 C,the template was amplified for 40 cycles of denaturation programed for 20 s at 95 C, annealing of primers at 60 C programed for 20 s, and extension at 72 C programed for 30 s. Fluorescent data were acquired during each extension phase. Each assay includes triplicate samples for each tested cDNAs and no-template negative control