The Reelin (RELN) gene encoding an extracellular matrix glycoprotein is an important protein for brain development and synaptic plasticity. Reelin protein has been found in various tissues and body fluids including brain, blood, spinal cord, and liver. A number of genome wide association studies and SNP analysis have shown a strong association of this SNP with schizophrenia, bipolar disorder, depression, Alzheimer’s disease and other mental health issues. Studies carried out on post-mortem samples have shown reduced or lower levels of reelin in brains of bipolar disorder and schizophrenia patients. There are thousands SNPs present on chromosome 7q22 where the RELN gene spans 517.7 kb and in an upstream region there is a CpG island which can also be hyper / hypo methylated which could contribute to the lower expression of reelin in brain.
The heterozygous reeler mouse studies have shown reelin’s involvement in psychotic disorders. Although there were no physical abnormalities there was behavioural changes such as delayed pre-pulse inhibition, attenuated methamphetamine-induced hyper-locomotion which are some of the signs observed in patients with psychotic disorders. In mice, over expression of reelin acts as an anti-depressant and the over-expressing strain was more resilient to stressful environments compared to wild types. In this study we collected DNA samples and analysed clinical depression and resilience scores from 141 subjects. The DNA samples were analysed for RELN SNP rs362719 using the qPCR-HRM method and validated by using restriction digested and sequence confirmed samples as controls (wild type, heterozygous mutant and homozygous mutant). In this preliminary study we were not able to show an association between SNP rs362719 with either depression or resilience, however further analysis on a larger samples size is required to allow a greater number of variables to be included.