Studies Explore Genetic Factors Underlying Depression
Research finds clues to antidepressant response, depression in adults mistreated in childhood
FRIDAY, Sept. 11 (HealthDay News) -- Multiple genetic factors may help predict patient response to antidepressants, and a haplotype in the CRHR1 gene may help protect individuals who were subjected to childhood mistreatment from depression in adulthood, according to the results of two studies published in the September Archives of General Psychiatry.
In the first study, Guilherme Polanczyk, M.D., of Duke University in Durham, N.C., and colleagues analyzed data from a group of 1,116 women in the E-Risk Study and 1,037 men and women in the Dunedin Study. In the first group, women reported on childhood mistreatment using the Childhood Trauma Questionnaire. Mistreatment was measured using a different method in the second group. In the first group, a TAT haplotype formed by rs7209436, rs110402, and rs242924 in CRHR1 was associated with a protective effect against depression, supporting earlier research, but this finding wasn't seen in the other group.
In the second study, Marcus Ising, Ph.D., of the Max Planck Institute of Psychiatry in Munich, Germany, and colleagues discuss the results of a genome-wide association study in 339 inpatients with a depressive episode and two replication studies in individuals with depression or major depression. Analysis revealed a binary variable that grouped patients into carriers of a high or low number of response alleles in predicting the outcome of antidepressant treatment in two samples.
"The present results demonstrate the importance of multiple genetic factors in the prediction of antidepressant drug response, which underscores the multifactorial nature of this trait. In particular, these findings imply a cumulative effect of genetic variations and clinical features. Both types of variables contributed similar effects with respect to prediction of treatment outcome," Ising and colleagues conclude.