The risk of developing CAN is not associated with the APOE ε2/ε2, APOE ε2/ε3, APOE ε2/ε4, APOE ε3/ε3, APOE ε3/ε4, or APOE ε4/ε4 isoforms in the Kazakh population. This evidence concerns the gene APOE and Crouzon syndrome-acanthosis nigricans syndrome.