Influence of neuronal cell adhesion molecule (NCAM1) variants on suicidal behaviour and correlated traits

Suicide is a public health problem all around the world. Family studies showed a strong heritability but, to date, few genetic data are available. Thus, in the present study we investigated whether a panel of single nucleotide polymorphisms (SNPs) in neuronal cell adhesion molecule 1 (NCAM) 1 was associated with suicidal behaviour as well as specific traits related to suicide. A total of two hundred and fifty-nine individuals with a positive history of suicidal behaviour and 312 healthy subjects were enrolled in the study. Rs2301228, rs1884, rs1245113, rs1369816, rs2196456 and rs584427 in NCAM1 were genotyped. No marker was significantly associated with suicidal behaviour vs. controls or with sub-types of attempted vs. completed, violent vs. non-violent, impulsive vs. non-impulsive suicide. Nonetheless rs1884 and rs2196456 SNPs were both marginally associated with the trait “inhibition of aggressiveness” in suicide attempters. Even though the investigated SNPs in NCAM1 do not seem to be directly associated with suicidal behaviour, our results could suggest that SNP variants in NCAM1 may impact on related traits, particularly by mediating inhibition of aggressiveness. However, independent studies are needed to validate these results.