The central nervous system patterning gene variants associated with clinical symptom severity of autism spectrum disorders.

BACKGROUND/PURPOSE: Central nervous system (CNS) patterning genes are recognized as candidate genes for autism spectrum disorders (ASDs) based on neuroimaging and neuropathological evidence. Several genes that regulate CNS development are shown to be associated with ASD. Our previous family-based association study also revealed that a specific haplotype of WNT2 (wingless-type MMTV integration site family member 2) gene was overtransmitted to probands with ASD. Whether the CNS patterning genes moderate the clinical phenotype of ASD is unclear. This study investigated the genetic associations of WNT2, engrailed 2 (EN2), and forkhead box P2 (FOXP2) with the clinical symptom severity. METHODS: The sample included 391 patients (males, 88.3%; mean age±standard deviation, 9.5±4.4 years) diagnosed with ASDs. Tag single nucleotide polymorphisms (SNPs) of EN2, WNT2, and FOXP2 were genotyped. The single-locus and multilocus markers were tested for association. RESULTS: We found that multilocus markers of WNT2 were associated with stereotyped behaviors whereas the markers of FOXP2 tended to be associated with social deficits. Moreover, an SNP of WNT2 showed a trend to be associated with less inattentive symptoms. CONCLUSION: Our findings that WNT2 and FOXP2 may moderate the clinical phenotypes of ASD provide evidence to support the possible universal effect of WNT2 and FOXP2 on neurodevelopmental symptom dimensions. Such findings warrant further validation in other independent samples. TRIAL REGISTRATION: Clinical trial registration identifier: NCT00494754.

Case review analysis of operating room decisions to cancel surgery.

BACKGROUND: Cancellation of surgery close to scheduled time causes a waste of healthcare resources. The current study analyzes surgery cancellations occurring after the patient has been prepared for the operating room, in order to see whether improvements in the surgery planning process may reduce the number of cancellations. METHODS: In a retrospective chart review of operating room surgery cancellations during the period from 2006 to 2011, cancellations were divided into the following categories: inadequate NPO; medical; surgical; system; airway; incomplete evaluation. The relative use of these reasons in relation to patient age and surgical department was then evaluated. RESULTS: Forty-one percent of cancellations were for other than medical reasons. Among these, 17.7% were due to incomplete evaluation, and 8.2% were due to family issues. Sixty seven percent of cancelled cases eventually received surgery. The relative use of individual reasons for cancellation varied with patient age and surgical department. The difference between cancellations before and after anesthesia was dependent on the causes of cancellation, but not age, sex, ASA status, or follow-up procedures required. CONCLUSION: Almost half of the cancellations were not due to medical reasons, and these cancellations could be reduced by better administrative and surgical planning and better communication with the patient and/or his family.

The effect of OPRM1 and COMT genotypes on the analgesic response to intravenous fentanyl labor analgesia.

BACKGROUND: IV fentanyl is used as a labor analgesic; however, few studies have reported the effects of IV fentanyl for early labor analgesia. We evaluated the analgesic response to IV fentanyl according to the combined effect of the single-nucleotide polymorphisms rs1799971 (c.118A/G, p. 40Asn/Asp) of the µ-opioid receptor gene (OPRM1) and rs4680 (c.472G/A, p.158Val/Met) of the catechol-O-methyltransferase (COMT) gene in women requesting labor analgesia. METHODS: Labor analgesia was initiated with IV fentanyl 1.5 µg/kg. The primary outcome was analgesic success, defined as Numerical Verbal Pain Scale score≤10/100 15 minutes after the dose of fentanyl. Analgesic and side effect outcomes were compared according to OPRM1 and COMT genotypes. RESULTS: One hundred six women were enrolled and received IV fentanyl. IV analgesic success was 6% in women with the combination Asn/Asn-Met/Met (n=17) versus 20% in all other women combined (not Asn/Asn-Met/Met; P=0.30; difference=14%; 95% confidence interval [CI], -10% to 26%). IV analgesic success was 20% in women 118A/A (Asn/Asn) versus 21% for A/G and G/G of OPRM1 (P=0.82; difference=2%; 95% CI, -17% to 19%), and 10% in women 472A (Met/Met) versus 22% for A/G (Met/Val) and G/G (Val/Val) of COMT (P=0.24; difference=12%; 95% CI, -6% to 26%). Met/Met158 (n=31) versus Met/Val or Val/Val of COMT was associated with a smaller decrease in Numerical Verbal Pain Scale (24±18 vs 37±23; P=0.005; mean difference=-13; 99% CI, -25 to -1). CONCLUSION: This study was underpowered to draw firm conclusions on the influence of OPRM1 and COMT genotypes on labor analgesia with IV fentanyl. Further larger studies are needed to evaluate whether genotyping COMT alone or in combination with OPRM1 may have potentially useful clinical implications, such as not offering IV fentanyl in early labor to women who will most likely not benefit from it.

Psychometric properties of the Chinese version of Strength and Difficulties Questionnaire.

This study aimed to establish the norms and to examine the psychometric properties of the Chinese version of the Strengths and Difficulties Questionnaire (SDQ). Sample included a representative sample of 3534 students (grades 1 to 8) from one city and one suburb each in Northern and Southern Taiwan by using a multistage sampling method and 211 psychiatric outpatients diagnosed with attention-deficit hyperactivity disorder (ADHD), aged 6 to 15, consecutively recruited from a medical center in Taipei. All the parents and teachers and participants with grade 4 or higher completed the SDQ. Parents and teachers also completed the Child Behavior Checklist and the measures about inattention, hyperactivity, and oppositional symptoms. Similar to Western studies, principal component analyses confirmed the five psychological dimensions of the SDQ for the parent, teacher, and student forms. The three forms of the Chinese SDQ showed satisfactory test-retest reliability, internal consistency, concurrent validity, and discriminant validity. All the subscales of the three forms of the Chinese SDQ clearly distinguished clinical participants with ADHD from school-based participants. Like Western studies, our findings indicate that the Chinese SDQ demonstrates a reliable and valid instrument for measuring internalizing, externalizing, and prosocial behaviors in Taiwanese child and adolescent population.

Chromosomal abnormalities in patients with autism spectrum disorders from Taiwan.

Autism spectrum disorders (ASD) are childhood-onset neurodevelopmental disorders characterized by verbal communication impairments, social reciprocity deficits, and the presence of restricted interests and stereotyped behaviors. Genetic factors contribute to the incidence of ASD evidently. However, the genetic spectrum of ASD is highly heterogeneous. Chromosomal abnormalities contribute significantly to the genetic deficits of syndromic and non-syndromic ASD. In this study, we conducted karyotyping analysis in a sample of 500 patients (447 males, 53 females) with ASD from Taiwan, the largest cohort in Asia, to the best of our knowledge. We found three patients having sex chromosome aneuploidy, including two cases of 47, XXY and one case of 47, XYY. In addition, we detected a novel reciprocal chromosomal translocation between long arms of chromosomes 4 and 14, designated t(4;14)(q31.3;q24.1), in a patient with Asperger's disorder. This translocation was inherited from his unaffected father, suggesting it might not be pathogenic or it needs further hits to become pathogenic. In line with other studies, our study revealed that subjects with sex chromosomal aneuploidy are liable to neurodevelopmental disorders, including ASD, and conventional karyotyping analysis is still a useful tool in detecting chromosomal translocation in patients with ASD, given that array-based comparative genomic hybridization technology can provide better resolution in detecting copy number variations of genomic DNA.

Combined Programmed Intermittent Bolus and Patient-Controlled Bolus Is a More Favorable Setting for Epidural Pain Relief Than Continuous Infusion.

Epidural analgesia is a suitable and effective treatment for labor pain. However, the preferable modality setting for delivery remains debatable. This study adopted a programmed intermittent epidural bolus (PIEB) setting in conjunction with a patient-controlled epidural analgesia (PCEA) setting to improve the quality of labor analgesia and reduce the number of medical staff. We conducted a prospective observational analysis of primigravida parturients scheduled for spontaneous labor, which required epidural analgesia for painless labor. A total of 483 healthy primigravida parturients with singleton pregnancies were included in this cohort; 135 nulliparous patients were assigned to the continuous infusion setting (CEI) group and 348 to the PIEB + PCEA group. Compared to the CEI setting, the PIEB + PCEA setting significantly reduced the manual rescue by the clinician, extended the time required for the first manual rescue dose, and acclaimed good maternal satisfaction. The use of the CEI mode increased for poor performance requiring more than two rescues with an odds ratio of 2.635 by a binary logistic regression analysis. Using the PIEB + PCEA setting as the maintenance infusion had a longer duration for the first requested manual rescue, fewer manual rescue boluses, excellent satisfaction, and no significant increase in adverse events compared to the CEI setting.

Total sleep deprivation augments balloon angioplasty-induced neointimal hyperplasia in rats.

Sleep deprivation has been shown to be associated with an increase in inflammation that is also involved in the development of neointimal hyperplasia (or restenosis). The purpose of this study was to investigate whether total sleep deprivation (TSD) would worsen neointimal formation by balloon injury. Sixteen rats were randomly allocated into the following four groups: group 1, balloon angioplasty alone; group 2, TSD prior to angioplasty; group 3, angioplasty before TSD; and group 4, TSD before and after angioplasty. Total sleep deprivation was induced by the disc-over-water method, and balloon angioplasty was performed in the carotid artery. Histopathological analysis and assay of cytokines were applied to evaluate the effects of TSD in this study. Total sleep deprivation significantly increased the ratio of postinjury neointima-to-media area in groups 2, 3 and 4 (all P < 0.01) compared with group 1. Additionally, in all groups with TSD administration the serum level of interleukin 10 was also markedly decreased on day 3 after angioplasty injury (P < 0.05 or P < 0.01). Our findings suggest that perioperative TSD can significantly augment neointimal hyperplasia of the carotid artery in rats, which may be partly caused by a TSD-induced effect in suppressing the serum level of the anti-inflammatory cytokine, interleukin 10.

The effect of maternal and fetal ß2-adrenoceptor and nitric oxide synthase genotype on vasopressor requirement and fetal acid-base status during spinal anesthesia for cesarean delivery.

BACKGROUND: Previous work demonstrated that maternal haplotypes of the ß2-adrenoceptor gene (ADRB2) influence ephedrine requirements during cesarean delivery. The use of ephedrine versus a pure α-adrenergic agonist such as phenylephrine has been associated with lower umbilical artery (UA) pH, thought to be secondary to increased fetal metabolism. There are no data evaluating the effect of fetal/neonatal genotypes on the metabolic response to maternally administered vasopressors. We hypothesized that neonatal ADRB2 genotype would affect the extent of neonatal acidemia. We also examined the effect of maternal ADRB2 and the endothelial nitric oxide synthase gene (NOS3) on ephedrine and phenylephrine requirements for treatment of maternal hypotension. METHODS: The study was performed on 104 Chinese women scheduled for cesarean delivery under spinal anesthesia who were participating in a double-blind randomized clinical trial evaluating the maternal and neonatal effects of ephedrine versus phenylephrine infusions. Blood samples were drawn from the UA, umbilical vein, and maternal radial artery to measure blood gas values and lactate, ephedrine, and phenylephrine concentrations, and to determine maternal and neonatal genotype at nonsynonymous single nucleotide polymorphisms at codons 16 (rs1042713) and 27 (rs1042714) of ADRB2 and codon 298 (rs1799983) of NOS. Clinical variables (UA pH, UA lactate, and dose of vasopressors) among genotypes were compared, and regression models were created to assess the effect of genotype on vasopressor dose and fetal acid-base status. RESULTS: Maternal ADRB2 genotype did not affect the ephedrine dose. Neonatal genotype at codon 16 influenced fetal acid-base status. UA pH was higher in Arg16 homozygous neonates (7.31 ± 0.03 in p.16Arg/Arg vs. 7.25 ± 0.11 in p.16 Arg/Gly and p.16 Gly/Gly; P < 0.001, 95%confidence interval (CI) of difference 0.03 ~ 0.09) and UA lactate was lower (2.67 mmol/L ± 0.99 in p.16Arg/Arg vs 4.28 mmol/L ± 2.79 in. p.16 Arg/Gly and p.16 Gly/Gly; P < 0.001, 95% CI of difference -2.40 ~ -0.82). In neonates born to mothers receiving ephedrine, the magnitude of the difference among genotypes was even greater (pH 7.30 ± 0.02 in p.16Arg/Arg vs. 7.19 ± 0.10 in p.16 Arg/Gly and p.16 Gly/Gly; P < 0.001, 95% CI of difference 0.07 ~ 0.14) and UA lactate was lower (3.66 mmol/L ± 1.30 in p.16Arg/Arg vs. 5.79 mmol/L ± 2.88 in p.16 Arg/Gly and p.16 Gly/Gly; P = 0.003, 95% CI of difference -3.48 ~ -0.80). In a multiple linear regression model (R² = 63.6%; P = 0.03), neonatal ADRB2 genotypes (p.16Arg/Arg and p.27Gln/Glu) and lower neonatal birth weight predicted lower UA lactate concentrations. Phenylephrine dose was not affected by maternal ADRB2 or NOS3 genotypes, and neonatal NOS3 genotype did not affect UA pH or UA lactate. CONCLUSION: In contrast to previous findings in a North American cohort, maternal ADRB2 genotype did not affect ephedrine requirements during elective cesarean delivery in a Chinese cohort. However, our findings suggest that neonatal ADRB2 p.Arg16 homozygosity confers a protective effect against developing ephedrine-induced fetal acidemia.

Higher systemic inflammation is associated with poorer sleep quality in stable haemodialysis patients.

BACKGROUND: Increased inflammation has been noted in sleep disorder patients with normal renal function. However, the relationship between sleep quality and circulating inflammatory markers has not been previously studied in haemodialysis (HD) patients. METHODS: A total of 114 HD end-stage renal disease patients receiving maintenance HD for >3 months were included in this study. Pittsburgh Sleep Quality Index (PSQI) was used to measure individual's sleep quality. Based on the global PSQI score, patients were divided into groups of good sleepers (PSQI < 5) and bad sleepers (PSQI >or= 5). RESULTS: Twenty-three patients (20.2%) were classified as good sleepers and 91 patients (79.8%) were bad sleepers. Bad sleepers have significantly higher serum hsCRP level and lower serum phosphate level (all P < 0.05). The global PSQI score, or worse sleep quality are positively correlated with serum triglyceride level, high-sensitivity C-reactive protein (hsCRP) level, IL-1beta level and negatively correlated with the haemoglobin and phosphate level. In the multi-variable linear regression model, levels of hsCRP (beta = 0.209, P = 0.029) and triglyceride (beta = 0.212, P = 0.025) were both significant independent predictors for the global PSQI score. CONCLUSION: Our study demonstrated severe impairment of sleep quality in HD patients and corroborated the role of inflammation in the pathogenesis of sleep disturbance.

Psychometric properties of the Chinese version of the Swanson, Nolan, and Pelham, Version IV Scale-Teacher Form.

OBJECTIVES: To examine the psychometric properties of the Chinese version of Swanson, Nolan and Pelham IV Scale (SNAP-IV)-Teacher Form. METHODS: The sample included a representative sample of 3,653 first to eighth graders (boys, 52.3%) and 190 children diagnosed with ADHD (aged 6-15). Teachers completed the Chinese versions of the SNAP-IV, and Strengths and Difficulties Questionnaire. RESULTS: The confirmatory factor analysis revealed a four-factor structure (inattention, hyperactivity, impulsivity, and opposition) with an adequate fit (Comparative Fit Index = 0.990; root mean square error of approximation = 0.058). The test-retest reliability (intraclass correlations = 0.60-0.84), internal consistency (alpha = .88-.95), and concurrent validity (Pearson correlations = 0.61-0.84) were satisfactory. Children with both ADHD and oppositional defiant/conduct disorders had the highest scores, followed by children with ADHD only who had intermediate scores and then school-based participants who had the lowest scores. CONCLUSIONS: Our findings suggest that the Chinese SNAP-IV-Teacher Form is a reliable and valid instrument for rating ADHD and oppositional symptoms (ClinicalTrials.Gov number, NCT00491361).

Complete atrioventricular block during thoracic endovascular aortic repair.

Acute coronary syndrome (ACS) and acute aortic syndrome (AAS) are both life-threatening emergencies. We report a case of ACS with thoracic aneurysm. Thoracic endovascular aortic repair (TEVAR) was arranged. However, perioperative complete atrioventricular block occurred and soon progressed to ST-elevation myocardial infarction. In the case of chest discomfort with elevated troponin I and thoracic aneurysm, it is of tremendous importance to cope with both ACS and the possible AAS. In the era of hybrid operation room, coronary catheterization and intervention first followed by TEVAR may provide timely and more comprehensive treatment.

Psychometric properties of the Chinese version of the Swanson, Nolan, and Pelham, version IV scale - parent form.

This study aimed to establish the psychometric properties of parent ratings on the Chinese version of the Swanson, Nolan, and Pelham IV scale (SNAP-IV) in a school-based sample of 3534 students in grades 1 to 8 from two cities and two suburbs in Taiwan and 189 children diagnosed with attention deficit/hyperactivity disorder (ADHD) (aged 6 to 15) consecutively recruited from a medical center in Taipei. Parents completed the Chinese versions of the SNAP-IV, Strengths and Difficulties Questionnaire, and Child Behavior Checklist. The Chinese SNAP-IV demonstrated similar three factor structure (Inattention, Hyperactivity/Impulsivity, and Oppositional) as its English version, and satisfactory test-retest reliability (intraclass correlation = 0.59 approximately 0.72), internal consistency (alpha = 0.88 approximately 0.90), concurrent validity (Pearson correlations = 0.56 approximately 0.72), and discriminant validity. Boys scored higher than girls across the eight school grade levels. The SNAP-IV clearly distinguished children with ADHD from school-based participants. Comorbidity with oppositional defiant disorder/conduct disorder predicted higher SNAP-IV scores among children with ADHD. Our findings suggest that the Chinese SNAP-IV is a reliable and valid instrument for rating ADHD-related symptoms in both clinical and community settings in Taiwan.

A single nucleotide polymorphism fine mapping study of chromosome 1q42.1 reveals the vulnerability genes for schizophrenia, GNPAT and DISC1: Association with impairment of sustained attention.

BACKGROUND: The marker D1S251 of chromosome 1q42.1 showed significant association with schizophrenia in a Taiwanese sample. We used single nucleotide polymorphism (SNP) fine mapping to search for the vulnerability genes of schizophrenia. METHODS: We selected 120 SNPs covering 1 Mb around D1S251 from the public database. These selected SNPs were initially validated if allele frequency was >10%. Forty-seven validated SNPs were genotyped in 102 families with at least 2 siblings affected with schizophrenia. RESULTS: Two SNP blocks showed significant association with schizophrenia. Block 1 (five-SNP), located between intron 2 and intron 13 of the glyceronephosphate O-acyltransferase (GNPAT) gene, showed the most significant associations using single-locus TDT (z = -2.07, p = .038, df = 1) and haplotype association analyses (z = -1.99, p = .046, df = 1). Block 2 (two-SNP), located between intron 4 and intron 5 of the disrupted-in-schizophrenia 1 (DISC1) gene, also showed the most significant results in both the single-locus (z = -3.22, p = .0013, df = 1) and haplotype association analyses (z = 3.35, p = .0008, df = 1). The association of the DISC1 gene with schizophrenia was mainly in the patient group with sustained attention deficits as assessed by the Continuous Performance Test. CONCLUSIONS: Chromosome 1q42.1 harbors GNPAT and DISC1 as candidate genes for schizophrenia, and DISC1 is associated with sustained attention deficits.

Genome scan of Han Chinese schizophrenia families from Taiwan: confirmation of linkage to 10q22.3.

OBJECTIVE: Genome-wide linkage analyses of schizophrenia have identified several regions that may harbor schizophrenia susceptibility genes, but given the complex etiology of the disorder, it is unlikely that all susceptibility regions have been detected. To address this issue, the authors ascertained 606 Han Chinese families comprising 1,234 affected members. METHOD: Probands with schizophrenia were recruited from six data collection field research centers in Taiwan. Each proband underwent a diagnostic screen with supplemental medical records and a semistructured interview. Following this screen, the authors administered the Mandarin Chinese version of the Diagnostic Interview for Genetic Studies. Best-estimate final diagnoses were made by two board-certified psychiatrists. The genotyping was conducted by the Center for Inherited Disease Research, with 386 markers spaced at an average of 9-centimorgan (cM) intervals. Empirical simulations were generated to determine genome-wide significance. RESULTS: The authors found five regions with nonparametric linkage z scores 2.0 or greater. These were the following: 2.08 was reached for D1S551 (113.7) cM at 1p31.1 and 2.31 for D2S410 (125.2 cM) at 2q14.1; 2.00 was reached for D4S2361 (93.5 cM) at 4q21.23, and 2.07 for D15S1012 (36 cM) at 15q14, the largest nonparametric linkage z score was 2.88 for D10S2327 (100.92 cM) at 10q22.3. CONCLUSIONS: Our 10q22.3 finding at 100.9 cM is consistent with a previously reported nonparametric linkage score of 4.27 at 107.2 cM on chromosome 10, although it did not attain genome-wide significance in this study.

No association of G72 and D-amino acid oxidase genes with schizophrenia.

The genes of D-amino acid oxidase (DAAO) activator (DAOA or G72; 13q34) and DAAO (12q24) have been suggested as candidate genes and involved in the N-methyl-D-aspartate receptor regulation pathway for schizophrenia. In order to evaluate the potential association of these two genes with schizophrenia in a Taiwanese sample, three single nucleotide polymorphisms (SNPs) for DAAO (rs2111902, rs3918346, rs3741775) and eleven SNPs for G72 (rs3916965, rs3916966, rs3916967, rs2391191, rs3916968, rs947267, rs778294, rs3916970, rs3916971, rs778293, rs3918342) were genotyped by the MALDI-TOF mass spectrometry method in 218 families (864 individuals) containing at least two siblings affected with schizophrenia. In SNP-based single locus association analyses, neither G72 nor DAAO showed significant association with schizophrenia. Additionally, a three-SNP haplotype in DAAO, and a four-SNP as well as a two-SNP haplotype in G72, showed no significant associations with schizophrenia. These results suggest that the DAAO and G72 genes are not susceptibility genes for schizophrenia in a Taiwanese sample.

Absence of significant associations between four AKT1 SNP markers and schizophrenia in the Taiwanese population.

AKT1 (V-akt murine thymoma viral oncogene homolog 1) is a protein kinase isoform of AKT. Five single-nucleotide polymorphisms, rs3803300, rs1130214, rs3730358, rs2498799 and rs2494732, at the genomic region of AKT1 have been reported to be significantly associated with schizophrenia. We tested for the presence of these five single-nucleotide polymorphisms in a Taiwanese population by genotyping 218 co-affected schizophrenia families. Both single locus and haplotypes analyses showed no association of these single-nucleotide polymorphisms with schizophrenia. These findings fail to support AKT1 as a susceptibility gene for schizophrenia in the Taiwanese population.

Genome-Wide Association Study for Autism Spectrum Disorder in Taiwanese Han Population.

BACKGROUND: Autism spectrum disorder (ASD) is a neurodevelopmental disorder with strong genetic components. Several recent genome-wide association (GWA) studies in Caucasian samples have reported a number of gene regions and loci correlated with the risk of ASD--albeit with very little consensus across studies. METHODS: A two-stage GWA study was employed to identify common genetic variants for ASD in the Taiwanese Han population. The discovery stage included 315 patients with ASD and 1,115 healthy controls, using the Affymetrix SNP array 6.0 platform for genotyping. Several gene regions were then selected for fine-mapping and top markers were examined in extended samples. Single marker, haplotype, gene-based, and pathway analyses were conducted for associations. RESULTS: Seven SNPs had p-values ranging from 3.4~9.9*10-6, but none reached the genome-wide significant level. Five of them were mapped to three known genes (OR2M4, STYK1, and MNT) with significant empirical gene-based p-values in OR2M4 (p = 3.4*10(-5)) and MNT (p = 0.0008). Results of the fine-mapping study showed single-marker associations in the GLIS1 (rs12082358 and rs12080993) and NAALADL2 (rs3914502 and rs2222447) genes, and gene-based associations for the OR2M3-OR2T5 (olfactory receptor genes, p = 0.02), and GLIPR1/KRR1 gene regions (p = 0.015). Pathway analyses revealed important pathways for ASD, such as olfactory and G protein-coupled receptors signaling pathways. CONCLUSIONS: We reported Taiwanese Han specific susceptibility genes and variants for ASD. However, further replication in other Asian populations is warranted to validate our findings. Investigation in the biological functions of our reported genetic variants might also allow for better understanding on the underlying pathogenesis of autism.

DAT polymorphism and diverse clinical manifestations in methamphetamine abusers.

The clinical outcome for methamphetamine (MAP) abusers is variable. MAP exerts its biological activity through rapid conversion to amphetamine (AP) and MAP itself. The dopamine transporter (DAT) is the main modulator of MAP/AP-induced dopamine release and dopamine neurotoxicity, and is also the major regulator of dopamine level in the brain. We tested for an association between a DAT-gene polymorphism and clinical variations in MAP abusers. A total of 146 MAP abusers were enrolled in the study and classified into three clinically distinct groups: MAP dependence (n = 30), MAP psychosis (n = 88) and chronic MAP psychosis (n = 28). Patients with schizophrenia (n = 79) and healthy controls (n = 72) were also recruited for the study. The 40 base pair variable number tandem repeat polymorphism in the 3'-untranslated region of the DAT was the focus of the investigation. The subjects were all Chinese residents of Taiwan. The respective allelic frequencies for DAT repeats 11, 10 and 9 were 0.067, 0.833 and 0.083 for the MAP-dependence group, 0.006, 0.864 and 0.119 for the MAP psychosis group, 0.018, 0.893 and 0.089 for the chronic MAP psychosis group, 0.019, 0.911 and 0.07 for the schizophrenic controls, and 0.021, 0.889 and 0.083 for the healthy controls. No significant associations were demonstrated between this DAT polymorphism in genotype and allele frequency and the clinical outcome of MAP abusers. The biological relevance of the variable number tandem repeat polymorphism in the 3'-untranslated region of DAT in MAP abusers was not demonstrated in this study.

Genetic analysis of GABRB3 as a candidate gene of autism spectrum disorders.

BACKGROUND: GABRB3 is a position candidate gene at chromosome 15q12 that has been implicated in the neurobiology of autism spectrum disorders (ASD). The aim of this study was to examine the genetic association of GABRB3 with ASD. METHODS: The sample consisted of 356 patients with clinical diagnosis of ASD according to the DSM-IV diagnostic criteria and confirmed by the Autism Diagnostic Interview-Revised and 386 unrelated controls. We searched for mutations at all the exonic regions and 1.6 Kb of the 5' region of GABRB3 in the genomic DNA of all the participants using the Sanger sequencing. We implemented a case-control association analysis of variants detected in this sample, and conducted a reporter gene assay to assess the functional impact of variants at the 5' regulatory region. RESULTS: We detected six known common SNPs; however, they were not associated with ASD. Besides, a total of 22 rare variants (12 at 5' regulatory, 4 at intronic, and 6 at exonic regions) were detected in 18 patients and 6 controls. The frequency of rare variants was significantly higher in the patient group than in the control group (18/356 versus 6/386, odds ratio = 3.37, P = 0.007). All the 12 rare variants at the 5' regulatory region were only detected in 7 patients, but not in any of the controls (7/356 versus 0/386, Fisher's exact test, P = 0.006). Two patients carried multiple rare variants. Family studies showed that most of these rare variants were transmitted from their parents. Reporter gene assays revealed that four rare variants at the 5' regulatory region and 1 at exon 1a untranslated region had elevated reporter gene activities compared to two wild type alleles. CONCLUSIONS: Our data suggest rare variants of GABRB3 might be associated with ASD, and increased GABRB3 expression may contribute to the pathogenesis of ASD in some patients. TRIAL REGISTRATION: CLINICAL TRIAL REGISTRATION IDENTIFIER: NCT00494754.