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D Souery

Publications and source records attributed to D Souery.

At least 19 recordsLinked to original sources

In search of anticipation in unipolar affective disorder.

Controversial evidence exists regarding the presence of the phenomenon of anticipation in affective disorder. To further evaluate this hypothesis on the unipolar pattern of the disease, we examined 21 two-generation pairs of first and second degree relatives with unipolar recurrent major depression. Biases from index-patient and from unaffected sibs were taken into consideration. A significant difference in the age at onset and episode frequency (as measure of disease severity) between parental and offspring generation was observed. The median age at onset of the parental generation was 37+/-8.2 years compared to 22+/-8.3 years in the offspring generation (p=0.001). The offspring generation also experienced an episode frequency two times greater than the parent generation (p=0.001). Anticipation was demonstrated in 95% of pairs regarding age at onset and in 84% of pairs in episode frequency. However, the observation of a birth cohort effect may possibly explain the differences in age at onset between generations in our sample.

Adolescent↗

Association between COMT (Val158Met) functional polymorphism and early onset in patients with major depressive disorder in a European multicenter genetic association study.

The available data from preclinical and pharmacological studies on the role of the C-O-methyl transferase (COMT) support the hypothesis that abnormal catecholamine transmission has been implicated in the pathogenesis of mood disorders (MD). We examined the relationship of a common functional polymorphism (Val108/158Met) in the COMT gene, which accounts for four-fold variation in enzyme activity, with 'early-onset' (EO) forms (less than or equal to 25 years) of MD, including patients with major depressive disorder (EO-MDD) and bipolar patients (EO-BPD), in a European multicenter case-control sample. Our sample includes 378 MDD (120 EO-MDD), 506 BPD (222 EO-BPD) and 628 controls. An association was found between the high-activity COMT Val allele, particularly the COMT Val/Val genotype and EO-MDD. These findings suggest that the COMT Val/Val genotype may be involved in EO-MDD or may be in linkage disequilibrium with a different causative polymorphism in the vicinity. The COMT gene may have complex and pleiotropic effects on susceptibility and symptomatology of neuropsychiatric disorders.

Age Factors↗

Social adjustment and self-esteem of bipolar patients: a multicentric study.

The aim of the present study was to investigate impairment in social adjustment and self-esteem of bipolar patients (n=144) in remission for at least 3 months. Patients were recruited among four different centres: Sofia, Athens, Jerusalem and Milan, and were individually matched to control subjects in relation to sex, age and geographical origin. Subjects completed the Rosenberg self-esteem scale (SES) and the self-report version of the social adjustment scale (SAS). Bipolar patients reported to experience more difficulties in social adjustment than controls, specifically for leisure and work activities. Further, our results show that bipolar patients have significantly lower self-esteem compared to controls, even after remission.

Adult↗

A major SNP haplotype of the arginine vasopressin 1B receptor protects against recurrent major depression.

Increasing amounts of data suggest that affective disorders might be related to dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, one of the stress-response systems. Arginine vasopressin (AVP) influences several symptoms, relevant to affective disorders, notable memory processes, pain sensitivity, synchronization of biological rhythms and the timing and quality of REM sleep. We examined whether genetic variations in the AVP receptor 1b gene (AVPR1b) could be associated with increased susceptibility to affective disorders using a gene-based association analysis of single-nucleotide polymorphisms (SNPs). Five SNPs were identified in AVPR1b and genotyped in two well-diagnosed samples of patients with recurrent major depression and matched controls. In the Swedish sample, we observed significant allele (P=0.02) and genotype (P=0.01) association with SNP AVPR1b-s3, and in the Belgian sample, a borderline significant association with SNP AVPR1b-s5 (P=0.04). In both patient-control samples, the haplotype defined by alleles A-T-C-A-G for the AVPR1b-s SNPs s1-s2-s3-s4-s5 was significantly over-represented in controls compared to patients. Our data support a protective effect of this major haplotype for recurrent major depression.

Aged↗

A novel CpG-associated brain-expressed candidate gene for chromosome 18q-linked bipolar disorder.

We previously identified 18q21-q22 as a candidate region for bipolar (BP) disorder and constructed a yeast artificial chromosome (YAC) contig map. Here we identified three potential CpG islands using CCG/CGG YAC fragmentation. Analysis of available genomic sequences using bioinformatic tools identified an exon of 3639 bp downstream of a CpG island of 1.2 kb containing a putative transcription initiation site. The exon contained an open reading frame coding for 1212 amino acids with significant homology to the SART-2 protein; weaker homology was found with a series of sulphotransferases. Alignment of cDNA sequences of corresponding ESTs and RT-PCR sequencing predicted a transcript of 9.5 kb which was confirmed by Northern blot analysis. The transcript was expressed in different brain areas as well as in multiple other peripheral tissues. We performed an extensive mutation analysis in 113 BP patients. A total of nine single nucleotide polymorphisms (SNPs) were identified. Five SNPs predicted an amino acid change, of which two were present in BP patients but not in 163 control individuals.

Amino Acid Substitution↗

Self-esteem, social adjustment and suicidality in affective disorders.

Self-esteem (SE) and social adjustment (SA) are often impaired during the course of affective disorders; this impairment is associated with suicidal behaviour. The aim of the present study was to investigate SE and SA in unipolar or bipolar patients in relation to demographic and clinical characteristics, especially the presence of suicidality (ideation and/or attempt). Forty-four patients, 28 bipolar and 16 unipolar, in remission for at least 3 months, and 50 healthy individuals were examined through a structured clinical interview. SE and SA were assessed by the Rosenberg self-esteem scale and the social adjustment scale, respectively. The results have shown that bipolar patients did not differ from controls in terms of SE, while unipolar patients had lower SE than bipolars and controls. No significant differences in the mean SA scores were found between the three groups. Suicidality during depression was associated only in bipolar patients with lower SE at remission; similar but not as pronounced was the association of suicidality with SA. It is concluded that low SE lasting into remission seems to be related to the expression of suicidality during depressive episodes of bipolar patients, while no similar pattern is evident in unipolar patients.

Adult↗

Excess of allele1 for alpha3 subunit GABA receptor gene (GABRA3) in bipolar patients: a multicentric association study.

The available data from preclinical and pharmacological studies on the role of gamma amino butyric acid (GABA) support the hypothesis that a dysfunction in brain GABAergic system activity contributes to the vulnerability to bipolar affective disorders (BPAD). Moreover, the localization of the alpha3 subunit GABA receptor GABRA3 gene on the Xq28, a region of interest in certain forms of bipolar illness, suggests that GABRA3 may be a candidate gene in BPAD. In the present study, we tested the genetic contribution of the GABRA3 dinucleotide polymorphism in a European multicentric case-control sample, matched for sex and ethnogeographical origin. Allele and genotype (in females) frequencies were compared in 185 BPAD patients and 370 controls. A significant increase of genotype 1-1 was observed in BPAD females compared to controls (P=0.0004). Furthermore, when considering recessivity of allele 1 (females with genotype 1-1 and males carrying allele 1), results were even more significant (P= 0.00002). Our findings suggest that the GABRA3 polymorphism may confer susceptibility to or may be in linkage disequilibrium with another gene involved in the genetic etiology of BPAD.

Alleles↗

[The psychiatry department].

The Department of Psychiatry was first opened in April 1978. It is one of the largest sector of the hospital and contains 90 beds including a sleep laboratory and an adolescent unit. The clinical activities are broad and multidisciplinary, including novel psychopharmacological and psychotherapeutic and psychosocial approaches. Educational and research activities have also been developed, in particular in the areas of behavioral genetics, sleep physiology, brain imaging and psychosocial research and training.

Belgium↗

Tryptophan hydroxylase polymorphism and suicidality in unipolar and bipolar affective disorders: a multicenter association study.

BACKGROUND: Being the rate-limiting enzyme in the biosynthesis of serotonin, the tryptophan hydroxylase gene (TPH) has been considered a possible candidate gene in bipolar and unipolar affective disorders (BPAD and UPAD). Several studies have investigated the possible role of TPH polymorphisms in affective disorders and suicidal behavior. METHODS: The TPH A218C polymorphism has been investigated in 927 patients (527 BPAD and 400 UPAD) and their matched healthy control subjects collected within the European Collaborative Project on Affective Disorders. RESULTS: No difference of genotype distribution or allele distribution was found in BPAD or UPAD. No statistically significant difference was observed for allele frequency and genotypes counts. In a genotype per genotype analysis in UPAD patients with a personal history of suicide attempt, the frequency of the C-C genotype (homozygosity for the short allele) was lower in UPAD patients (24%) than in control subjects (43%) (chi(2) = 4.67, p =.03). There was no difference in allele or genotype frequency between patients presenting violent suicidal behavior (n = 48) and their matched control subjects. CONCLUSIONS: We failed to detect an association between the A218C polymorphism of the TPH gene and BPAD and UPAD in a large European sample. Homozygosity for the short allele is significantly less frequent in a subgroup of UPAD patients with a history of suicide attempt than in control subjects.

Alleles↗

Molecular genetic and family studies in affective disorders: state of the art.

The identification of genes responsible for mood disorders will contribute to significant advances in the awareness of diagnosis (diagnostic process and early recognition), pathophysiology, epidemiology and treatment issues. During the past two decades, the search for genes for mood disorders has mainly contributed to better understand and confirm the genetic complexities inherent to these disorders. The large amount of results available and the difficulty to digest them corroborate this observation. The major contribution of these findings should be integrated in the context of the world-wide efforts to identify the thousands of genes of the human genome. Some of these genes may be identified within the next decade. Several consistent hypotheses are currently being tested and will, hopefully, speed up the process of narrowing the important regions when the complete genome map will be available. The most promising chromosomal regions have been localized on chromosomes 4, 5, 11, 12, 18, 21 and X. A number of candidate genes have also been investigated, some of these are directly linked to neurobiological hypotheses of the aetiology of affective disorders. In parallel, specific hypotheses have been implicated, such as anticipation and dynamic mutations. Further research should concentrate on these hypotheses and confirm positive findings through interdisciplinary and multicenter projects.

Anticipation, Genetic↗

Lack of association between GABRA3 and unipolar affective disorder: a multicentre study.

Available data on gamma amino butyric acid (GABA) support the hypothesis that a dysfunction in the brain GABAergic system activity contributes to vulnerability to affective disorders (AD), including bipolar disorder (BPAD) and unipolar disorder (UPAD). The localization of the alpha3 subunit GABA receptor (GABRA3) gene in Xq28, a region of interest for BPAD suggests that GABRA3 may be a relevant candidate gene. In the present study, we tested the genetic contribution of the GABRA3 dinucleotide polymorphism in a European multicentre UPAD case-control sample [UPAD (n = 106), controls (n = 212)]. Our negative results suggest that GABRA3 does not confer susceptibility nor is it in linkage disequilibrium with another close gene involved in the genetic aetiology of UPAD.

Adult↗

Variability of 5-HT2C receptor cys23ser polymorphism among European populations and vulnerability to affective disorder.

Substantial evidence supports a role for dysfunction of brain serotonergic (5-HT) systems in the pathogenesis of major affective disorder, both unipolar (recurrent major depression) and bipolar.(1) Modification of serotonergic neurotransmission is pivotally implicated in the mechanism of action of antidepressant drugs(2) and also in the action of mood stabilizing agents, particularly lithium carbonate.(3) Accordingly, genes that code for the multiple subtypes of serotonin receptors that have been cloned and are expressed in brain,(4) are strong candidates for a role in the genetic etiology of affective illness. We examined a structural variant of the serotonin 2C (5-HT2C) receptor gene (HTR2C) that gives rise to a cysteine to serine substitution in the N terminal extracellular domain of the receptor protein (cys23ser),(5) in 513 patients with recurrent major depression (MDD-R), 649 patients with bipolar (BP) affective disorder and 901 normal controls. The subjects were drawn from nine European countries participating in the European Collaborative Project on Affective Disorders. There was significant variation in the frequency of the HT2CR ser23 allele among the 10 population groups included in the sample (from 24.6% in Greek control subjects to 9.2% in Scots, chi(2) = 20.9, df 9, P = 0.01). Logistic regression analysis demonstrated that over and above this inter-population variability, there was a significant excess of HT2CR ser23 allele carriers in patients compared to normal controls that was demonstrable for both the MDD (chi(2) = 7.34, df 1, P = 0.006) and BP (chi(2) = 5.45, df 1, P = 0.02) patients. These findings support a possible role for genetically based structural variation in 5-HT2C receptors in the pathogenesis of major affective disorder.

Amino Acid Substitution↗

5-HT2a receptor polymorphism gene in bipolar disorder and harm avoidance personality trait.

The purpose [corrected] of this study was to investigate the relationship between bipolar disorder and the harm avoidance personality trait (HA), and the genetic contribution of the polymorphic DNA variation T102C in exon 1 of 5-HTR2a (chromosome 13q14-21) in bipolar disorder and HA personality trait. Forty bipolar patients and 89 normal subjects completed the TPQ questionnaire and were genotyped for 5-HT2a. Bipolar patients scored higher than normal subjects on the HA dimension. However, no contribution of the 5-HTR2a polymorphism on the bipolar disorder or on the HA personality trait emerged. Despite the limited sample size, these results exclude a major effect of the 5-HTR2a polymorphism on bipolar disorder and HA personality trait but not a minor effect.

Adult↗

A European multicenter association study of HTR2A receptor polymorphism in bipolar affective disorder.

The available data on the role of 5-HT in a variety of behaviors support the hypothesis that a dysfunction in brain serotoninergic system activity contributes to vulnerability to major depression. The diversity in the electrophysiological actions of 5-HT in the central nervous system can now be categorized according to receptor subtypes and their respective effector mechanisms. In particular, the implication of central postsynaptic 5-HT2A receptor in affective disorders has been supported by findings consistent with the hypothesis of 5-HT2A receptor up-regulation in depression. For these reasons, the 5-HT2A receptor (HTR2A) gene can be considered as a candidate gene in bipolar affective disorder (BPAD). We tested the possible genetic contribution of the polymorphic DNA variation T102C in exon 1 of HTR2A (chromosome 13q14-21) gene in a large European multicentric case-control sample. Allele and genotype frequencies, as well as homo-heterozygote distributions were compared between the two groups of 309 bipolar affective disorder patients and 309 matched controls. No significant differences were observed in the allelic and genotypic (also for homo-heterozygote) distribution between BPAD and controls. These results indicate that, in our sample, the 5-HT2A receptor polymorphism studied is unlikely to play a major role in the genetic susceptibility to BPAD. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:136-140, 2000.

Adult↗

Linkage of mood disorders with D2, D3 and TH genes: a multicenter study.

BACKGROUND: It has been suggested that the dopaminergic system is involved in the pathophysiology of mood disorders. We conducted a multicenter study of families with mood disorders, to investigate a possible linkage with genes coding for dopamine receptor D2, dopamine receptor D3 and tyrosine hydroxylase (TH). METHODS: Twenty three mood disorder pedigrees collected within the framework of the European Collaborative Project on Affective Disorders were analyzed with parametric and non-parametric linkage methods. Various potential phenotypes were considered, from a narrow (only bipolar as affected) to a broad (bipolar+major depressive+schizoaffective disorders) definition of affection status. RESULTS: Parametric analyses excluded linkage for all the candidate genes, even though small positive LOD (Limit of Detection) scores were observed for TH in three families. Non-parametric analyses yielded negative results for all markers. CONCLUSION: The D2 and D3 dopamine receptors were, therefore, not a major liability factor for mood disorders in our sample, whereas TH may play a role in a subgroup of patients.

Bipolar Disorder↗

No evidence for the involvement of CAG/CTG repeats from within 18q21.33-q23 in bipolar disorder.

We previously identified 18q21.33-q23 as a candidate region in one BP family and constructed a yeast artificial chromosome (YAC) contig map. Here, we mapped eight known CAG/CTG repeats relative to 18q21.33-q23. We also isolated four CAG/CTG repeats from within the region using CAG/CTG YAC fragmentation, one of which is located in the 5' untranslated region of the CAP2 gene coding for a brain-expressed serine proteinase inhibitor. The triplet repeats located in the 18q21.33-q23 BP candidate region showed no expanded alleles in the linked BP family nor in a BP case-control sample. Moreover, only the CAP2 triplet repeat was polymorphic but no genetic association with BP disorder was observed.

Bipolar Disorder↗

Tyrosine hydroxylase polymorphism and phenotypic heterogeneity in bipolar affective disorder: a multicenter association study.

Tyrosine hydroxylase (TH), the rate-limiting enzyme in the metabolism of catecholamines, is considered a candidate gene in bipolar affective disorder (BPAD) and has been the subject of numerous linkage and association studies. Taken together, most results do not support a major gene effect for the TH gene in BPAD. Genetic and phenotypic heterogeneity may partially explain the difficulty of confirming the exact role of this gene using both association and linkage methods. Four hundred one BPAD patients and 401 unrelated matched controls were recruited within a European collaborative project (BIOMED1 project in the area of brain research, European Community grant number CT 92-1217, project leader: J. Mendlewicz) involving 14 centers for a case-control association study with a tetranucleotide polymorphism in the TH gene. Patients and controls were carefully matched for geographical origin. Phenotypic heterogeneity was considered and subgroup analyses were performed with relevant variables: age at onset, family history, and diagnostic stability. No association was observed in the total sample or for subgroups according to age at onset (n = 172), family history alone (n = 159), or high degree of diagnostic stability and a positive family history (n = 131). The results of this association study do not confirm the possible implication of TH polymorphism in the susceptibility to BPAD.

Adult↗