For example, an immigration study revealed that APOA1 polymorphisms and patterns are common among people with Asian ethnicity, but the patterns and polymorphisms differ from those reported in European Caucasians.46 To explain why the racial difference of APOA1/C3/A4/A5 copy number loss manifested in young patients but not in old patients, we hypothesize that the increasing lipid intake in young East Asian women with gene polymorphisms of impaired lipid metabolism contributes to a higher incidence rate of breast cancer with APOA1/C3/A4/A5 copy number loss. This evidence concerns the gene APOA1 and breast cancer.