The documentation of higher cord blood levels of IGF-1 among Caucasian compared with Asian newborns is concordant with the higher incidence of breast cancer in western compared with eastern Asian populations (Ferlay et al, 2004) and compatible with the role IGF appears to play in breast cancer, at least among premenopausal women (Renehan et al, 2004; Schernhammer et al, 2005). This evidence concerns the gene IGF1 and breast cancer.