The Genetic Base of Depression

3 (ADAA n. p). On the other hand, ADAA points that this depressive disorder affects close to 16. 1 million individuals adults, a figure projected to be 6. 7% of the population 18 years and older within a year (n. Landmark studies on the genetic impact and moderations on the effects of life stressors on depression have however revealed that the gene-environment interactions in psychopathology have made significant discoveries. In these studies, people presenting one or more short alleles within the serotonin transporter gene (5-HTTLPR) promoter are considered as vulnerable to the contraction of MDD. Genes are no longer anonymous or an omnibus, but identifiable and specific, an aspect that has spawned a new approach of investigating depression and other psychopathological diseases as well as the critical biological structures and processes that mediate and influence genes and gene actions (Whittemore 267).

The claims and allegations that genes are vital in different depressive disorders to remain an aspect that is well substantiated. When an adopter suffering from MDD is compared to the parents, it is evident that the disease may have been collectively shared twice as much the number of times prevalently through a biological parent as opposed to the adopted parent (Monroe, Scott, & Mark 948). The GWAS methods have over the years produced significant results that help in accruing insights into some of the biological pathways convoluted in diseases susceptibility for mental health disorders. However, GWAS method has been met by several limitations since they have failed in revealing the candidate genes, an aspect that is attributed to the fact that the effect sizes of polymorphism are somehow smaller, an element that means this could be a locus shared by BD and MDD.

Another major limitation of GWAS models in depression is evident in popular candidate genes that have over the past shown no evidence in the association. It is essential to point out that before the GWAS era, meta-analytical processes for candidate gene studies made contributions in identifying the nominal significant evidence for six different candidate genes in depression as SLC6A4, MTHFR, GNB3, DRD4, APOE, and SLC6A3. However, Lewis posits that none of these genes have provided evidence of their significant associations in the GWAS model to date. Preclinical Studies on Animals The inclusion of animal models in the study of psychiatric disorders remains a challenging approach in as much as its impact remains of the essence. In other words, the development of animal models is depicting psychiatric disorders presents challenges due to the poor understanding of some of the pathophysiological and etiopathogenetic elements of such diseases (Bras et al.