Molecular Genetics of Mood Disorders - Essay Example

It is also possible that different variants of genes are responsible to cause depression in each family. (Nestler et al.,2002)The association of the location of the TPH2 (Tryptophan hydroxylase) gene and the role of serotonin is being widely described and is also associated with depression.

The TPH gene is responsible for depressive disorders and suicidal tendencies. The researchers have also indicated the role of the hydroxy indole acetic acids in Cerebrospinal fluid which is significant in suicidal tendencies. The location of the serotonin transporter gene and the role of its polymorphism is significant in suicidal tendencies. (Kamrowska A., 2007).In 1999 Silber et al, studied the possible causes of greater depression among adolescent girls by examining variation in the influence of genetic and environmental risk factors among 182 prepubertal females, 237 prepubertal males, 314 pubertal female, and 171 pubertal male twin pairs.

The patients were from the Virginia Twin Study of Adolescent Behavioral Development. The impact of life events on depression was particularly evident in adolescent girls. The results clearly indicated that the increased heritability for depression in this group and its lifelong consistency clearly indicated that it was largely mediated by genetic factors. The researchers could also perform model fitting which also showed that at least part of the liability to depression and to life events was linked to a common set of genes in the adolescent girls, and there was a notable developmental increase in the genetic variance for life events.

The role of dysregulation of beta-serotonin (5-HT) neurotransmission is also known to be responsible for depression, anxiety disorders, bipolar disorder, autism, etc.