GRM4 and bone cancer: Studies have shown that GRM5 is upregulated in lung and glial cancers,20, 21 and inactivation of GRM5 suppresses liver and bone cancer cell proliferation by blocking mitogen‐activated protein kinase pathways.22, 23 The intronic variants rs701332 located in GRM3, and rs2499707 and rs4713742 located in GRM4, were associated with the survival of RCC patients.