Abstract
Introduction: The aim of this study was to investigate the variance components in TP53 mRNA expression after in vivo exposure to double threshold dose of ultraviolet radiation B (UVR-B). Methods: Twelve six-week-old female albino Sprague-Dawley rats were exposed to double threshold dose (8 kJ/m2) of UVR-B unilaterally and sacrificed at 1, 3, 8, and 24 h after exposure. Lenses were enucleated, and TP53 mRNA expression was detected by qRT-PCR. Variance components for groups, animals, and measurements were estimated with analysis of variance. Results: The variance for groups is 0.15 rel.2. The variance for animals is 0.29 rel.2. The variance for measurements is 0.32 rel.2. Conclusion: The variance for animals is in the same order as the variance for measurements. The reduction of the variance for measurements is needed in order to obtain the acceptable level of detection of the difference in TP53 mRNA expression and the reduction in sample size.