These eight probes for the CHST14, COL14A1, CREB3L2, FGF23, INF2, KAT6B, ADAMTS7 and XYLT1 genes showed significantly higher methylation levels for at least three CpG sites in CS samples than in healthy controls (Fig. 1c). This evidence concerns the gene XYLT1 and Cowden syndrome 1.