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Velocardiofacial syndrome (VCFS) is caused by a microdeletion in chromosome 22 and is a risk factor for the development of schizophrenia and other psychiatric disorders. The catechol-O-methyltransferase (COMT), residing in the 22q11.2 microdeletion region, is a major candidate gene for genetic susceptibility to neuropsychiatric disorders in VCFS. Individuals with VCFS carrying the low-activity allele (COMTL) are expected to have the lowest possible COMT activity since they have only a single copy of the gene. We explored the possibility that COMTL is associated with psychiatric disorders commonly found in VCFS. Fifty-five unrelated individuals with VCFS underwent psychiatric evaluation and were genotyped for the COMT 158Val/Met polymorphism coding for COMT high/low-activity alleles. The COMTL allele was significantly more prevalent in VCFS subjects with attention deficit hyperactivity disorder (ADHD) (73.9% vs. 33.3%, OR 5.67, chi2=7.76, p=0.005) and obsessive-compulsive disorder (OCD) (78.6% vs. 33.3%, OR 7.33, chi2=7.24, p=0.007) than in the control group (VCFS subjects without OCD, ADHD and schizophrenia/schizoaffective (SZ/SZaff) disorder). The results of this study suggest that greatly reduced COMT activity, as expected in VCFS COMTL individuals may be a risk factor for psychiatric sequelae in this population. Future longitudinal studies focusing on additional COMT polymorphic sites and other candidate genes from the deleted region will elucidate the molecular pathways leading to schizophrenia and other psychiatric disorders in VCFS.

The "phospholipid hypothesis" attributes a pathophysiologic role to the polyunsaturated fatty acid (PUFA) composition of phospholipids in depression. The aim of the present study was to determine whether the hypothesis is relevant to social anxiety disorder (SAD). The study sample consisted of 27 untreated, nondepressed patients with SAD (DSM-IV) and 22 controls. Severity of SAD was assessed with the Liebowitz Social Anxiety Scale (LSAS). Erythrocyte PUFA concentrations were measured by gas-liquid chromatography. Concentrations of most n-3 PUFAs were lower in the patients: 18:3n-3 by 32% (p < 0.002), 20:3n-3 by 34%, 20:5n-3 by 36% (all p < 0.001) and 22:6n-3 by 18% (p = 0.002). No significant differences were observed in other fatty acids. Significant inverse correlations were obtained between levels of n-3 PUFAs and LSAS scores. In conclusion, the phospholipid hypothesis may apply to SAD, thereby opening new therapeutic options. The robust relationship between low erythrocyte n-3 PUFA concentrations and SAD justifies exploration of relevant neuropathophysiological mechanisms.

Facial crowds of emotion connoting approval or criticism are linked to the fears of socially anxious individuals. We examined evaluation ratings and decision latencies of mixed facial displays by individuals with generalized social phobia (GSPs, n = 18), individuals with comorbid depression and GSP (COMs, n = 18), and normal controls (CONs, n = 18). First, we postulated that GSPs will assign more negative ratings to predominantly disapproving audiences as compared to CONs, and that GSPs will be faster in their evaluation of these audiences (negative bias hypothesis). Second, we expected depression, but not social anxiety, to be associated with diminished positive evaluation of audiences containing predominantly happy expressions and with a slower processing of such positive cues (the impaired positivity hypothesis). Results supported the negative bias hypothesis, and provided partial support for the impaired positivity hypothesis. The importance of examining the processing of complex non-verbal cues in social anxiety and in depression is discussed.

The study of neurogenetic microdeletion syndromes provides an insight into the developmental psychopathology of psychiatric disorders. The aim of the study was to evaluate the prevalence of psychiatric disorders, especially obsessive-compulsive disorder (OCD), in patients with velocardiofacial syndrome (VCFS), a 22q11 microdeletion syndrome. Forty-three subjects with VCFS of mean age 18.3 +/- 10.6 years were comprehensively assessed using semi-structured psychiatric interview and the Yale-Brown obsessive compulsive scale (Y-BOCS). Best estimate diagnoses were made on the basis of information gathered from subjects, parents, teachers, and social workers. Fourteen VCFS subjects (32.6%) met the DSM-IV criteria for OCD. OCD had an early age of onset and generally responded to fluoxetine treatment. It was not related to mental retardation. The most common obsessive-compulsive symptoms were contamination, aggression, somatic worries, hoarding, repetitive questions, and cleaning. Sixteen of the 43 patients (37.2%) had attention-deficit/hyperactivity disorder (ADHD), and 7 (16.2%) had psychotic disorder. The results of our study suggest that there is a strong association between VCFS and early-onset OCD. This finding may be significant in the understanding of the underlying genetic basis of OCD., (Copyright 2003 Wiley-Liss, Inc.)

Velocardiofacial syndrome (VCFS) is a relatively common developmental neuropsychiatric syndrome caused by a 22q11 microdeletion. There is an extensive variability in the phenotypic expression of this disease. The most common psychiatric disorder in VCFS is attention-deficit/hyperactivity disorder (ADHD), affecting 35-55% of patients. This study investigated the association of familial, developmental, and physical factors with the occurrence of ADHD in 51 patients with nonfamilial VCFS. Twenty-one patients (41.2%) were diagnosed with ADHD. There was a significantly greater prevalence of ADHD in the first-degree relatives of the patients with ADHD than in those without (OR = 5.9, 95% CI = 1.6-22.1, P = 0.006). No differences were noted between the ADHD and non-ADHD groups in mean Obstetric Complication Scale Score, gestational age, birth weight, age at first words, walking, and achieving bowel control. The two groups also had similar IQ scores (total, verbal, and performance) and had a similar average degree of severity of facial dysmorphism and cardiac and cleft anomalies. These findings indicate that ADHD in VCFS has a genetic contribution and the patients' VCFS-related developmental factors and physical illnesses play a lesser role., (Copyright 2003 Wiley-Liss, Inc.)

Background: Velocardiofacial syndrome (VCFS) is a common microdeletion syndrome associated with psychiatric morbidity and developmental disabilities. Although attention-deficit/hyperactivity disorder (ADHD) is the most common psychiatric problem associated with VCFS, there are no reports on methylphenidate treatment in this patient population. Indeed, clinicians have commonly avoided the use of methylphenidate in children with VCFS because of concerns about ineffectiveness or psychotic exacerbation., Method: Forty subjects of mean +/- SD age 11.0 +/- 5.0 years with VCFS were assessed for DSM-IV diagnoses using the Schedule for Affective Disorders and Schizophrenia for School-Aged Children, Present and Lifetime Version, and its extended ADHD module (K-SADS-P-ADHD). Those found to have comorbid ADHD were treated with methylphenidate, 0.3 mg/kg once daily. Treatment efficacy was evaluated after 4 weeks with the K-SADS-P-ADHD, the Conners' Abbreviated Teacher Questionnaire, and the Conners' Continuous Performance Test. Side effects were evaluated with a modified version of the Barkley Side Effects Rating Scale., Results: Of the 18 subjects (45%) diagnosed with ADHD, 12 agreed to participate in the study. Their ADHD symptoms, both behavioral and cognitive, improved significantly with treatment. None of the patients showed clinical worsening or psychotic symptoms. Side effects were usually mild and did not warrant discontinuation of methylphenidate. The most common side effects were anorexia and depressive-like symptoms., Conclusion: This open-label study indicates that methylphenidate is effective and safe in patients with VCFS. Therefore, its current limited use in this population seems to be unjustified. Larger, controlled clinical and pharmacogenetic studies are needed to confirm these findings.

Cannabinoid receptors have been implicated as having important roles in human cognitive processes, especially memory and attention. While some work has studied the effects of the active ingredient in marijuana, delta-9-tetrahydrocannabinol (THC), on short-term memory, no work has examined the involvement of these receptors in mediating attention. Therefore, the present study compared the effects of THC on the performance by rats of an operant spatial signal detection task with those of cholinergic muscarinic antagonist scopolamine and glutamatergic NMDA antagonist MK-801, both compounds known to influence attention and other cognitive processes in rats. These experiments were conducted in a two lever operant chamber in which a cue lamp was mounted over each lever. The rats were pretrained to respond rapidly on the corresponding lever following a rapid presentation of the cue lamp above it. The stimulus was presented in a random order of three durations (100, 300 or 1000 ms) to measure detectability of the stimulus under saline, THC (1.0 or 2.0 mg/kg i.p.), scopolamine (0.06-0.25 mg/kg i.p.), or MK-801 (0.06-0.25 mg/kg i.p.). THC significantly and selectively disrupted stimulus detection accuracy at the 100 ms stimulus duration, but did not influence response bias or the rate of responding. Scopolamine and MK-801 both produced alteration in errors of omission and position bias. These data suggest that THC produces an impairment in visual attention and that the nature of this impairment is qualitatively different from that produced by muscarinic-receptor or NMDA-receptor antagonism.