Obsessive-compulsive disorder (OCD) is a psychiatric disorder characterized by recurrent, intrusive and disturbing thoughts as well as by repetitive stereotypic behaviors. OCD is a complex disorder and its pathogenesis is most likely influenced by both genetic and environmental factors. Although more than 140 candidate gene studies have been conducted, the findings have been inconclusive due to small sample size and few study replications. Many studies suggest that abnormal serotonergic neurotransmission is one of the most consistent biological findings in OCD. Studies have also reported dopaminergic abnormalities in the basal ganglia and nucleus accumbens, as well as altered glutamate transmission. First line treatments for this disorder are cognitive behavioral therapy (exposure and response prevention) and selective serotonin reuptake inhibitors (SSRIs). In recent years, one of the promising novel treatment strategies developed to improve the efficacy of treatment for patients with OCD is acceptance and commitment therapy (ACT). Recent studies have suggested that age of onset is an important factor in subtyping OCD. Early-onset OCD has been proposed to be associated with greater symptom severity, a higher prevalence of tic-related disorders, a more familial form of the condition, and a greater prevalence of psychiatry disorders in first-degree relatives as compared to late-onset OCD.
Category
Mental and behavioural disorder
Brite
Human diseases in ICD-11 classification [BR:br08403]
06 Mental, behavioural or neurodevelopmental disorders
Obsessive-compulsive or related disorders
6B20 Obsessive-compulsive disorder
H01450 Obsessive-compulsive disorder
Pathway-based classification of diseases [BR:br08402]
Cellular process
nt06544 Neuroactive ligand signaling
H01450 Obsessive-compulsive disorder
Sampaio AS, Hounie AG, Petribu K, Cappi C, Morais I, Vallada H, do Rosario MC, Stewart SE, Fargeness J, Mathews C, Arnold P, Hanna GL, Richter M, Kennedy J, Fontenelle L, de Braganca Pereira CA, Pauls DL, Miguel EC
Title
COMT and MAO-A polymorphisms and obsessive-compulsive disorder: a family-based association study.
Major depressive disorder (MDD) is the most common psychiatric disorder mainly characterized by depressed mood, loss of interest, feelings of worthlessness, and a high risk of suicide. Accumulated evidence suggests that both environmental and genetic factors are involved in the etiology of MDD although the pathogenesis of MDD remains unknown. Mutations in genes involved in brain serotonin synthesis, have been identified in patients. Brain serotonin deficiency has been hypothesized to play a role in a wide range of psychiatric diseases, including MDD. Several efficacious treatments for MDD are available, including different forms of psychotherapy and antidepressant medication. Recently, selective reuptake inhibitors (SSRIs, SNRIs,) have become the first-line antidepressant drug treatment of depression and replaced tricyclic antidepressants (TCA) and monoamine oxidase inhibitors (MAOI) due to fewer side-effects and ease of use.
Category
Mental and behavioural disorder
Brite
Human diseases in ICD-11 classification [BR:br08403]
06 Mental, behavioural or neurodevelopmental disorders
Mood disorders
Depressive disorders
6A70 Single episode depressive disorder
H01646 Major depressive disorder
6A71 Recurrent depressive disorder
H01646 Major depressive disorder
Pathway-based classification of diseases [BR:br08402]
Amino acid metabolism
nt06028 Dopamine and serotonin metabolism
H01646 Major depressive disorder
Cellular process
nt06544 Neuroactive ligand signaling
H01646 Major depressive disorder
Schizophrenia (SCZD) is a common serious psychotic illness that typically emerges in late adolescence and early adulthood. It is characterized by hallucinations and delusions (commonly known as positive symptoms), social withdrawal, alogia, and flat affect (negative symptoms), and cognitive disabilities. While treatments exist for the psychotic symptoms of schizophrenia, there is no effective therapy to prevent the cognitive impairments. The disorder is substantially heritable, but expression of the clinical phenotype is likely to involve the interplay of multiple susceptibility variants, epigenetic factors, and environmental influences. Although it has been suggested that many of the promising candidate genes are involved in the development and maintenance of synaptic function, the most of them remains to be identified. The pathogenic mechanisms underlying schizophrenia are unknown, but observers have repeatedly noted pathological features involving excessive loss of gray matter and reduced numbers of synaptic structures on neurons. Recently, it has been found that alleles of the C4 genes are associated with schizophrenia in proportion to their tendency to promote greater expression of C4A in the brain.
Category
Mental and behavioural disorder
Brite
Human diseases in ICD-11 classification [BR:br08403]
06 Mental, behavioural or neurodevelopmental disorders
Schizophrenia or other primary psychotic disorders
6A20 Schizophrenia
H01649 Schizophrenia
Pathway-based classification of diseases [BR:br08402]
Cellular process
nt06544 Neuroactive ligand signaling
H01649 Schizophrenia
Zhao X, Tang R, Gao B, Shi Y, Zhou J, Guo S, Zhang J, Wang Y, Tang W, Meng J, Li S, Wang H, Ma G, Lin C, Xiao Y, Feng G, Lin Z, Zhu S, Xing Y, Sang H, St Clair D, He L
Title
Functional variants in the promoter region of Chitinase 3-like 1 (CHI3L1) and susceptibility to schizophrenia.
Chumakov I, Blumenfeld M, Guerassimenko O, Cavarec L, Palicio M, Abderrahim H, Bougueleret L, Barry C, Tanaka H, La Rosa P, Puech A, Tahri N, Cohen-Akenine A, Delabrosse S, Lissarrague S, Picard FP, Maurice K, Essioux L, Millasseau P, Grel P, Debailleul V, Simon AM, Caterina D, Dufaure I, Malekzadeh K, Belova M, Luan JJ, Bouillot M, Sambucy JL, Primas G, Saumier M, Boubkiri N, Martin-Saumier S, Nasroune M, Peixoto H, Delaye A, Pinchot V, Bastucci M, Guillou S, Chevillon M, Sainz-Fuertes R, Meguenni S, Aurich-Costa J, Cherif D, Gimalac A, Van Duijn C, Gauvreau D, Ouellette G, Fortier I, Raelson J, Sherbatich T, Riazanskaia N, Rogaev E, Raeymaekers P, Aerssens J, Konings F, Luyten W, Macciardi F, Sham PC, Straub RE, Weinberger DR, Cohen N, Cohen D
Title
Genetic and physiological data implicating the new human gene G72 and the gene for D-amino acid oxidase in schizophrenia.
Sekar A, Bialas AR, de Rivera H, Davis A, Hammond TR, Kamitaki N, Tooley K, Presumey J, Baum M, Van Doren V, Genovese G, Rose SA, Handsaker RE, Daly MJ, Carroll MC, Stevens B, McCarroll SA
Title
Schizophrenia risk from complex variation of complement component 4.
Mimmack ML, Ryan M, Baba H, Navarro-Ruiz J, Iritani S, Faull RL, McKenna PJ, Jones PB, Arai H, Starkey M, Emson PC, Bahn S
Title
Gene expression analysis in schizophrenia: reproducible up-regulation of several members of the apolipoprotein L family located in a high-susceptibility locus for schizophrenia on chromosome 22.
