Figure 9B showed the NMF matrix when k = 3, containing 13 samples in C1, 16 samples in C2, and 7 samples in C3. The expression patterns of endometriosis-related genes were visualized in Figure 9C. PCA further complemented the distinction among three subtypes at transcription levels (Figure 9D). Additionally, four characteristic genes: BGN and ELMO1 levels were the highest in C3, followed by C2 and C1 (Figure 9E); no significant differences in AQP1 and DDR2 were detected among three subtypes. Here, BGN is linked to endometriosis.