Epigenetic regulation of FGFR2 has also been studied, with FGFR2 promoter hypomethylation highlighted as a promising non-invasive biomarker for detecting gastric cancer and intestinal metaplasia: FGFR2 promoter methylation levels measured with MSRE-qPCR differ sharply between control groups (approximately 93% methylation levels), intestinal metaplasia groups (approximately 70% methylation levels), and gastric cancer groups (26 to 28% methylation levels). The gene discussed is FGFR2; the disease is gastric cancer.