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The following is a summary of “Genetic polymorphism involved in major depressive disorder: a systemic review and meta-analysis,” published in the October 2024 issue of Psychiatry by Suktas et al. 

Genetic polymorphism studies in families and twins have indicated the heritability of depression; however, the association between genes with genetic polymorphisms and major depressive disorder (MDD) yields varied and unclear findings. 

Researchers conducted a systematic review and meta-analysis to identify genes with polymorphisms associated with MDD. 

They searched PubMed and Scopus for studies published between 1968 and May 22, 2023, selecting 62 for review. Bias was assessed using the Newcastle–Ottawa scale. Gene functional enrichment analysis focused on molecular function (MF) and biological process (BP), and a meta-analysis was conducted using a random-effects model for the identified single nucleotide polymorphisms. 

The results showed that 49 genes involved in MDD engaged in pathways like tryptophan metabolism and dopaminergic and serotonergic synapses. Thirteen genes with polymorphisms were identified as related to MDD, with most studied only once. Solute carrier family 6 member 4 (SLC6A4) and brain-derived neurotrophic factor (BDNF) were included in the meta-analysis. The SLC6A4 SS and LS genotypes increased MDD risk but not significantly [OR = 1.39; 95% CI = 0.87–2.22; P = 0.16 and OR = 1.13; 95% CI = 0.84–1.53; P = 0.42, respectively]. Similar results were found for BDNF rs6265 GG (OR = 1.26; 95% CI = 0.78–2.06; P = 0.35) and AA genotypes (OR = 1.12; 95% CI = 0.77–1.64; P = 0.56). These studies indicated low bias and significant heterogeneity. 

The study concluded that at least 13 genes with polymorphisms were associated with MDD development, but their significance remains unclear, suggesting the need for interaction with other risk factors. 

Source: bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-024-06195-z#Abs1