title: Association of a corticotropin-releasing hormone receptor 1 haplotype and antidepressant treatment response in Mexican-Americans.
abstract: There are well-replicated, independent lines of evidence supporting a role for corticotropin-releasing hormone (CRH) in the pathophysiology of depression. CRH receptor 1 (CRHR1), which we first mapped in the brain in 1994, has been implicated in the treatment of depression and anxiety. We studied the association of CRHR1 genotypes with the phenotype of antidepressant treatment response in 80 depressed Mexican-Americans in Los Angeles who completed a prospective randomized, placebo lead-in, double-blind treatment of fluoxetine or desipramine, with active treatment for 8 weeks. Subjects were included into the study if they had a diagnosis of depression without other confounding medical or psychiatric diagnoses or treatments. All patients were followed weekly and assessed for changes in the Hamilton rating scales for anxiety (HAM-A) and depression (HAM-D). Inclusion criteria in the study included a HAM-D of 18 or higher. Because CRHR1 affects both depression and anxiety. Patients were classified into a high-anxiety (HA) group if their HAM-A score was 18 or higher and in a low-anxiety (LA) group if their HAM-A score was less than 18. Utilizing the haplotype-tag single-nucleotide polymorphisms rs1876828, rs242939 and rs242941, we tested for haplotypic association between CRHR1 and 8-week response to daily antidepressant treatment. In the HA group (n=54), homozygosity for the GAG haplotype was associated with a relative 70% greater reduction in HAM-A scores compared to heterozygous (63.1+/-4.5 vs 37.1+/-6.9%, respectively, P=0.002). For HAM-D, GAG haplotype homozygosity was associated with a 31% greater reduction in scores after treatment compared to heterozygous (67.3+/-4.3 vs 51.2+/-6.0%, respectively, P=0.03). In those with lower-anxiety levels at screening, there were no associations between CRHR1 genotype and percent change in HAM-A or HAM-D. These findings of increased response to antidepressants in highly anxious patients homozygous for the GAG haplotype of CRHR1 need to be independently validated and replicated. Such work would support the hypotheses that response to antidepressant treatment is heterogeneous and that the CRHR1 gene and possibly other genes in stress-inflammatory pathways are involved in response to antidepressant treatment. These findings also suggest that variations in the CRHR1 gene may affect response to CRHR1 agonists or antagonists. All data are deposited in www.pharmgkb.org.
authors.affiliation: Center for Pharmacogenomics and Clinical Pharmacology, Neuropsychiatric Institute, David Geffen School of Medicine, University of California, Los Angeles, CA 90095-1761, USA.
authors.forename: J
authors.initials: J
authors.lastname: Licinio
authors.forename: F
authors.initials: F
authors.lastname: O'Kirwan
authors.forename: K
authors.initials: K
authors.lastname: Irizarry
authors.forename: B
authors.initials: B
authors.lastname: Merriman
authors.forename: S
authors.initials: S
authors.lastname: Thakur
authors.forename: R
authors.initials: R
authors.lastname: Jepson
authors.forename: S
authors.initials: S
authors.lastname: Lake
authors.forename: K G
authors.initials: KG
authors.lastname: Tantisira
authors.forename: S T
authors.initials: ST
authors.lastname: Weiss
authors.forename: M-L
authors.initials: ML
authors.lastname: Wong
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use; D001007:Anxiety / Q000150:complications / Q000208:ethnology / Q000235:genetics*; D003866:Depressive Disorder / Q000150:complications / Q000188:drug therapy / Q000208:ethnology* / Q000235:genetics*; D003891:Desipramine / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D005473:Fluoxetine / Q000627:therapeutic use; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease / Q000208:ethnology; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D016555:Matched-Pair Analysis; D017058:Mexican Americans / Q000235:genetics* / Q000523:psychology; D011446:Prospective Studies; D018019:Receptors, Corticotropin-Releasing Hormone / Q000187:drug effects / Q000235:genetics*; D012016:Reference Values; D016896:Treatment Outcome; D000099052:CRF Receptor, Type 1
chemical_list: D000928:Antidepressive Agents; D005819:Genetic Markers; D018019:Receptors, Corticotropin-Releasing Hormone; D005473:Fluoxetine; D000099052:CRF Receptor, Type 1; D003891:Desipramine