Rs2237717 (major: C, minor: T) is located in intron 11 within the MET proto-oncogene. The MET gene is primarily known to be involved in tumor metastasis 
Given that schizophrenic patients have a lower incidence of cancer despite more exposure to risk factors and relatives without schizophrenia appear to also have a protective effect on cancer incidence, it has been hypothesized that alterations in cancer genes (like MET, containing rs2237717) may be involved in the pathogenesis of schizophrenia 
In a study by Burdick et al 
They also reported that the MET haplotype which was inversely correlated with schizophrenia (‘Block 3’ containing rs2237717) had a significant impact on neurocognition. Carriers of the major allele at rs2237717 in the comparison group performed significantly better than non-carriers on a test of general cognitive ability.
Association with facial emotional perception
Another study by Lin et al 
The MET gene has been implicated in nasal polyp development [PMID 19532090], and Castano et al [PMID 20416453] showed that the minor allele at rs2237717 is associated with chronic rhinosinusitis in patients with nasal polyps (genotypic P nominal = 0.09, empirical P = 0.04, OR = 1.4, CI = 1.0-1.9). This suggests that polymorphisms in the MET gene, including rs2237717, may play a role in the susceptibility to develop CRS. Study findings apply to patients with nasal polyps and severe CRS unresponsive to surgery.
[PMID 20080979] Association of genetic variation in the MET proto-oncogene with schizophrenia and general cognitive ability
[PMID 20416453] c-MET pathway involvement in chronic rhinosinusitis: a genetic association analysis
[PMID 19002214] MET and autism susceptibility: family and case-control studies.