title: Additive genetic contribution to symptom dimensions in major depressive disorder.
abstract: Major depressive disorder (MDD) is a phenotypically heterogeneous disorder with a complex genetic architecture. In this study, genomic-relatedness-matrix restricted maximum-likelihood analysis (GREML) was used to investigate the extent to which variance in depression symptoms/symptom dimensions can be explained by variation in common single nucleotide polymorphisms (SNPs) in a sample of individuals with MDD (N = 1,558) who participated in the National Institute of Mental Health Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. A principal components analysis of items from the Hamilton Rating Scale for Depression (HRSD) obtained prior to treatment revealed 4 depression symptom components: (a) appetite, (b) core depression symptoms (e.g., depressed mood, anhedonia), (c) insomnia, and (d) anxiety. These symptom dimensions were associated with SNP-based heritability (hSNP2) estimates of 30%, 14%, 30%, and 5%, respectively. Results indicated that the genetic contribution of common SNPs to depression symptom dimensions were not uniform. Appetite and insomnia symptoms in MDD had a relatively strong genetic contribution whereas the genetic contribution was relatively small for core depression and anxiety symptoms. While in need of replication, these results suggest that future gene discovery efforts may strongly benefit from parsing depression into its constituent parts. (PsycINFO Database Record
authors.affiliation: Institute for Mental Health Research, The University of Texas at Austin.
authors.forename: Rahel
authors.initials: R
authors.lastname: Pearson
authors.affiliation: Division of Behavioral Genetics, Department of Psychiatry, Rhode Island Hospital.
authors.forename: Rohan H C
authors.initials: RH
authors.lastname: Palmer
authors.affiliation: Division of Behavioral Genetics, Department of Psychiatry, Rhode Island Hospital.
authors.forename: Leslie A
authors.initials: LA
authors.lastname: Brick
authors.affiliation: Providence Veterans Affairs Medical Center.
authors.forename: John E
authors.initials: JE
authors.lastname: McGeary
authors.affiliation: Division of Behavioral Genetics, Department of Psychiatry, Rhode Island Hospital.
authors.forename: Valerie S
authors.initials: VS
authors.lastname: Knopik
authors.affiliation: Institute for Mental Health Research, The University of Texas at Austin.
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Beevers
mesh_terms: D000328:Adult; D003863:Depression / Q000150:complications / Q000235:genetics*; D003865:Major Depressive Disorder / Q000150:complications / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011569:Psychiatric Status Rating Scales