Polymerase chain reaction with confronting two-pair primers, high resolution melting and direct-sequencing results of MDM2 and p73 gene polymorphisms. (A) MDM2 polymorphisms: Three genotypes are indicated by arrows: TT, TG and GG. (B) p73 polymorphisms. Lanes 1 and 4, GC/GC genotype (428 and 193 bp); lanes 2 and 3, GC/AT genotype (428, 270 and 193 bp); and lanes 5 and 6, AT/AT genotype (428 and 270 bp). M, marker; MDM2, murine double minute 2.