Breast-cancer diagnosis using hair

James et al.1 observed a difference between the X-ray diffraction patterns of hair from healthy females and from breast-cancer patients. This difference was reported as the presence of an extra ring corresponding to a spacing of 4.44 nm on the patterns obtained from breast-cancer patients. This ring was also observed in patterns from subjects “not yet diagnosed with breast cancer but suspected of being at risk”. James et al. proposed that these observations might lead to a screening method for breast cancer. We have now repeated the study using a different hair type (from the scalp), but are unable to replicate their observations.