In contrast, genes consistently upregulated in male BC tissues included neuroligin 4 Y-linked (NLGN4Y), ribosomal protein S4 Y-linked 1 (RPS4Y1), protein kinase Y-linked (PRKY), ubiquitously transcribed tetratricopeptide repeat containing Y-linked (UTY), DEAD-box helicase 3 Y-linked (DDX3Y), eukaryotic translation initiation factor 1A Y-linked (EIF1AY), testis-specific transcript Y-linked 15 (TTTY15), and ubiquitin-specific peptidase 9 Y-linked (USP9Y) (Figure 1D). Here, PRKY is linked to breast cancer.