Serum FGF23 and renal Cyp24a1 mRNA abundance are increased in E1m−/+ mice. A, Serum FGF23 in wild-type (open circles) and E1m−/+ (filled circles) littermates. B, Whole kidney levels of Cyp24a1 and Cyp27b1 mRNA in wild-type and E1m−/+ littermates; n = 7 and 5 for Cyp24a1; n = 7 and 7 for Cyp27b1, respectively. Measurements were done by using qRT-PCR relative to β-actin and normalized to values obtained from control littermates; *, P < .05; **, P < .01; NS, not statistically significant.