| Although the majority of target genes studied [ class 1 : B 23 ( NPM 1 ) , CAD , CDK 4 , cyclin D 2 , ID 2 , LDH A , MNT , PTMa , ODC , NM23B , nucleolin , prohibitin , SHMT 1 , and SHMT 2 ] demonstrate significant sequence conservation of the E boxes and flanking regions , several genes ( cyclin B 1 , JPO 1 , and PRDX 3 ) belong to a second class ( class 2 ) that does not display sequence conservation at and around the site of c Myc binding . ^^^ |