GSTP1 and Familial prostate cancer: For example, Agalliu et al. 2006 reported a moderate increase in PCA risk associated with the GSTM1 gene deletion for Caucasian men (OR = 1.54; 95%CI = 1.19-2.01); however, GSTT1 deletion and GSTP1 105 Val polymorphisms were not significantly associated with prostate cancer[5].