Striatal dopamine D2/3 receptors in medication-naïve schizophrenia: an [123I] IBZM SPECT study.

BACKGROUND: The hyper-function of the striatal dopamine system has been suggested to underlie key pathophysiological mechanisms in schizophrenia. Moreover, patients have been observed to present a significant elevation of dopamine receptor availability compared to healthy controls. Although it is difficult to measure dopamine levels directly in humans, neurochemical imaging techniques such as single-photon emission computed tomography (SPECT) provide indirect indices of in vivo dopamine synthesis and release, and putative synaptic levels. METHODS: We focused on the role of dopamine postsynaptic regulation using [123I] iodobenzamide (IBZM) SPECT. We compared D2/3 receptor availability between 53 healthy controls and 21 medication-naive patients with recent-onset schizophrenia. RESULT: The mean specific striatal binding showed no significant difference between patients and controls (estimated difference = 0.001; 95% CI -0.11 to 0.11; F = 0.00, df = 1, 69; p = 0.99). There was a highly significant effect of age whereby IBZM binding declined with advancing age [estimated change per decade of age = -0.01(binding ratio); 95% CI -0.01 to -0.004; F = 11.5, df = 1, 69; p = 0.001]. No significant correlations were found between the mean specific striatal binding and psychopathological or cognitive rating scores. CONCLUSIONS: Medication-naïve patients with recent-onset schizophrenia have similar D2/3 receptor availability to healthy controls. We suggest that, rather than focusing exclusively on postsynaptic receptors, future treatments should target the presynaptic control of dopamine synthesis and release.

Heart Rate Variability with Deep Breathing in Drug-Naïve Patients with Schizophrenia.

Abnormal autonomic nervous system (ANS) function may result in poor outcomes in patients with schizophrenia. Altered cardio-respiratory coupling, which indicates suppression of vagal activity, was identified as an important trait in patients with schizophrenia and their unaffected relatives. Heart rate variability (HRV) in standardized bedside reflex tests has been studied, mostly in medicated patients with schizophrenia whose ANS function could be influenced by medication. Our study aimed to explore the autonomic function differences between drug-naïve patients with schizophrenia and healthy individuals during challenge tests combining respiration and HRV analysis. Forty-two drug-naïve patients with schizophrenia were matched with 42 healthy controls in terms of age and gender. Their beat-to-beat blood pressure and heart rate were monitored in the supine position as a survey of ANS function, and the mean heart rate range (MHRR) was measured under deep-breathing challenge. A decreased MHRR, a sensitive sign indicating an impaired parasympathetic response, during the deep-breathing challenge among the drug-naïve patients with schizophrenia was found. Drug-naïve patients with schizophrenia may have a parasympathetic dysfunction in the early stages of schizophrenia before medication is introduced, which could be considered a neurobiological marker in the pathophysiology of schizophrenia.

Heart Rate Variability is Associated with Memory in Females.

Research into the association between heart rate variability (HRV) and cognitive function is scarce, particularly with regard to gender differences. HRV in 182 healthy volunteers was assessed by the root mean square of the successive difference (RMSSD) and spectrum analysis, while the Wechsler Memory Scale-Revised (WMS-R) was used to determine memory function. Robust and significant associations were found to exist between HRV (RMSSD and high-frequency HRV) and domains of the WMS-R in females. Caution should therefore be taken to control for gender when conducting studies on the relationships between HRV and cognitive variables.

Genotype variant associated with add-on memantine in bipolar II disorder.

Memantine is a non-competitive N-methyl-d-asparate (NMDA) receptor antagonist with a mood-stabilizing effect. We investigated whether using valproic acid (VPA) plus add-on memantine to treat bipolar II disorder (BP-II) is more effective than using VPA alone (VPA + Pbo). We also evaluated, in BP-II patients, the association between the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism with treatment response to VPA + add-on memantine and to VPA + Pbo. In this randomized, double-blind, controlled 12 wk study, BP-II patients undergoing regular VPA treatments were randomly assigned to a group: VPA + Memantine (5 mg/day) (n = 115) or VPA + Pbo (n = 117). The Hamilton Depression Rating Scale (HDRS) and Young Mania Rating Scale (YMRS) were used to evaluate clinical response during week 0, 1, 2, 4, 8 and 12. The genotypes of the BDNF Val66Met polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis. To adjust within-subject dependence over repeated assessments, multiple linear regression with generalized estimating equation methods was used to analyze the effects of the BDNF Val66Met polymorphism on the clinical performance of memantine. Both groups showed significantly decreased YMRS and HDRS scores after 12 wk of treatment; the differences between groups were non-significant. When stratified by the BDNF Val66Met genotypes, significantly greater decreases in HDRS scores were found in the VPA + memantine group in patients with the Val Met genotype (p = 0.004). We conclude that the BDNF Val66Met polymorphism influenced responses to add-on memantine by decreasing depressive symptoms in patients with BP-II.

Gender-specific association of the SLC6A4 and DRD2 gene variants in bipolar disorder.

Findings on the association between the risk for developing bipolar disorder and the functions of the serotonin transporter-linked polymorphic region gene (5-HTTLPR) and dopamine D2 receptor gene (DRD2) variants are contradictory. One explanation for this is that a gender difference may exist for genetic contributions. We compared the gender-related main effects and the gene-to-gene interaction between serotonin transporter gene (SLC6A4) and DRD2 in adult male and female patients with bipolar I (BP-I) and bipolar II (BP-II) disorder. Patients with BP-I (n = 400) and BP-II (n = 493), and healthy controls (n = 442) were recruited from Taiwan's Han Chinese population. The genotypes of the 5-HTTLPR and DRD2 Taq-IA polymorphisms were determined using polymerase chain reaction-restriction fragment length polymorphism analysis. Logistic regression analysis showed a significant gender-specific association of the DRD2 A1/A1 and the 5-HTTLPR S/S, S/LG , and LG/LG (S+) (p = 0.01) genotypes in men with BP-I (p = 0.002 and 0.01, respectively) and BP-II (p = 0.001 and 0.007, respectively), but not in women. A significant interaction for the DRD2 A1/A1 and 5-HTTLPR S+ polymorphisms was also found only in men with BP-I and BP-II (p = 0.003 and 0.001, respectively). We provide preliminary evidence for a gender-specific effect of the SLC6A4 and DRD2 gene variants for the risk of BP-I and of BP-II. We also found gender-specific interaction between 5-HTTLPR and DRD2 Taq-IA polymorphisms in patients with bipolar disorder.

The effects of add-on low-dose memantine on cytokine levels in bipolar II depression: a 12-week double-blind, randomized controlled trial.

Memantine, a noncompetitive N-methyl-d-aspartate receptor antagonist with a mood-stabilizing effect, and an association between bipolar disorder and proinflammatory cytokine levels have been reported. Whether adding-on memantine would reduce cytokine levels and is more effective than valproic acid (VPA) alone in bipolar II disorder was investigated. A randomized, double-blind, controlled, 12-week study was conducted. Patients undergoing regular VPA treatments were randomly assigned to a group: VPA + memantine (5 mg/d) (n = 106) or VPA + placebo (n = 108). The Hamilton Depression Rating Scale (HDRS) and Young Mania Rating Scale (YMRS) were used to evaluate clinical response. Symptom severity, plasma tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), IL-8, and IL-1 levels were examined during weeks 0, 1, 2, 4, 8, and 12. To adjust within-subject dependence over repeated assessments, multiple linear regressions with generalized estimating equation methods were used to examine the therapeutic effect. Tumor necrosis factor α levels were significantly lower in the VPA + memantine group than in the VPA + placebo group (P = 0.013). Posttreatment HDRS and YMRS scores decreased significantly in both groups, but not significant, nor was the other between-group cytokine level difference pretreatment and posttreatment. The HDRS score changes were significantly associated with IL-6 (P = 0.012) and IL-1 (P = 0.005) level changes and changes in YMRS score changes with TNF-α (P = 0.005) level changes. Treating bipolar II depression with VPA + memantine may improve the plasma TNF-α level. However, adding-on memantine may not improve clinical symptoms or cytokine levels other than TNF-α. Clinical symptoms may be correlated with certain cytokines.

Venlafaxine, paroxetine and milnacipran for major depressive disorder: a pragmatic 24-week study.

Major depressive disorder (MDD), one of the most common psychiatric disorders in the world, is a serious, recurrent and chronic mental disorder, which is associated with significant psychosocial disability and economic burden. Until recently, short-term effectiveness of antidepressants has been measured in terms of patients' response to the medications in significantly reduced depressive symptoms. Remission, a long-term elimination of symptoms and the restoration of normal functioning, has become the primary outcome of therapy. In the current study, the efficacy of three frequently prescribed antidepressants, venlafaxine (75-225 mg/day), paroxetine (20 mg/day) and milnacipran (100 mg/day), used in treating 249 MDD patients with Hamilton Rating Scale of Depression (HRSD17) scores higher than 16 was compared. Each patient was evaluated at week 0, 1, 2, 4, 8, 12, 16, 20 and 24 in a 24-week open-label study. Eighty-two patients took venlafaxine, 97 took paroxetine and 70 patients took milnacipran. No significant differences were found between the three groups in the response condition (HRSD17 scores decreased more than 50%) after 24 weeks of follow-up. For remission, the paroxetine was the least efficacious medication than either the milnacipran (HRSD17 ≤ 7) or the venlafaxine (HRSD17 ≤ 5) by the last observation carried forward (LOCF) analysis. Our results suggest that the absence of depressive symptoms alone may not be an indicator for MDD remission, but the duration of absent depressive symptoms may be a better indicator.

Interaction between novelty seeking and the aldehyde dehydrogenase 2 gene in heroin-dependent patients.

OBJECTIVES: Heroin dependence is a multifactor disorder. We investigated the association of genetic factors and heroin-dependent temperaments to determine whether a temperament-gene interaction is involved in the pathogenesis of heroin dependence. METHODS: Three hundred seventy participants (259 heroin-dependent patients and 111 healthy controls) were recruited and finished the Tridimensional Personality Questionnaire to assess personality traits (temperament). The genotypes of the aldehyde dehydrogenase 2 (ALDH2) gene and the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene using polymerase chain reactions plus restriction fragment length polymorphism analysis. RESULTS: Multiple logistic regression analysis showed significant main effects for novelty seeking (P ≤ 0.001) and harm-avoidance (P = 0.001) scores, and a significant interaction effect between novelty seeking and ALDH2 genotypes (P = 0.016) in heroin-dependent patients compared with controls. When stratified by the ALDH2 genotypes, only heroin-dependent patients with the *1*2 and *2*2 genotypes at ALDH2 had higher novelty-seeking scores than did controls (heroin dependence = 15.94, controls = 12.46; P ≤ 0.001). CONCLUSIONS: Our results provide initial evidence that the ALDH2 gene interacted with novelty seeking in heroin-dependent Han Chinese patients in Taiwan.

Interaction between serotonin transporter and serotonin receptor 1 B genes polymorphisms may be associated with antisocial alcoholism.

BACKGROUND: Several studies have hypothesized that genes regulating the components of the serotonin system, including serotonin transporter (5-HTTLPR) and serotonin 1 B receptor (5-HT1B), may be associated with alcoholism, but their results are contradictory because of alcoholism's heterogeneity. Therefore, we examined whether the 5-HTTLPR gene and 5-HT1B gene G861C polymorphism are susceptibility factors for a specific subtype of alcoholism, antisocial alcoholism in Han Chinese in Taiwan. METHODS: We recruited 273 Han Chinese male inmates with antisocial personality disorder (ASPD) [antisocial alcoholism (AS-ALC) group (n=120) and antisocial non-alcoholism (AS-N-ALC) group (n=153)] and 191 healthy male controls from the community. Genotyping was done using PCR-RFLP. RESULTS: There were no significant differences in the genotypic frequency of the 5-HT1B G861C polymorphism between the 3 groups. Although AS-ALC group members more frequently carried the 5-HTTLPR S/S, S/LG, and LG/LG genotypes than controls, the difference became non-significant after controlling for the covarying effects of age. However, the 5-HTTLPR S/S, S/LG, and LG/LG genotypes may have interacted with the 5-HT1B G861C C/C polymorphism and increased the risk of becoming antisocial alcoholism. CONCLUSION: Our study suggests that neither the 5-HTTLPR gene nor the 5-HT1B G861C polymorphism alone is a risk factor for antisocial alcoholism in Taiwan's Han Chinese population, but that the interaction between both genes may increase susceptibility to antisocial alcoholism.

Schizotypy trait and striatal dopamine receptors in healthy volunteers.

Individuals with schizotypal features exhibit cognitive, perceptual and social deficits that are similar to but less prominent than those seen in patients with schizophrenia. Dopaminergic hyperactivity in the striatum has been related to the positive symptoms of schizophrenia, and brain-imaging studies of dopamine uptake in the striatum are thought to be linked to the pathophysiological mechanisms underlying schizophrenia. The aim of this study was to investigate whether the increased availability of striatal dopamine (DA) D(2/3) receptors is related to elevated levels of schizotypal features in healthy individuals. The Schizotypal Personality Questionnaire (SPQ) was administered to 55 healthy volunteers. The availability of their striatal DA D(2/3) receptors was analysed using [(123)I] iodobenzamide single photon emission computed tomography (SPECT). Although the SPQ total scores showed no correlation with the availability of total (left and right) striatal DA D(2) receptors, the SPQ disorganised subscale scores were positively correlated with the availability of right striatal DA D(2/3) receptors. Our findings demonstrated that the availability of striatal DA D(2/3) receptors may be associated with schizotypal features in healthy volunteers.

Daily life events influence the results of the Dexamethasone Suppression Test in healthy women.

Although the Dexamethasone Suppression Test (DST) plays an important role in psychosomatic research, confounding factors limit the sensitivity and specificity of the DST. The aim of this study was to investigate the relationship between the intensity of daily life stressors and DST results in healthy participants after controlling the confounding factors. The subjects of this study consisted of 75 healthy volunteers. The intensity of daily life events was assessed using the Taiwanese version of the Recent Life Change Questionnaire (RLCQ). Neuroticism was assessed using the Maudsley Personality Inventory (MPI). The Dexamethasone Suppression Test (DST) was also performed. The regression model showed that daily life events (RLCQ score) were correlated significantly with cortisol level on day 1 and D% only in women. This finding implies that daily life events should be considered as an independent variable in women in further studies when the DST is applied.

Comparison of the validity of the Chinese versions of the Hypomania Symptom Checklist-32 (HCL-32) and Mood Disorder Questionnaire (MDQ) for the detection of bipolar disorder in medicated patients with major depressive disorder.

OBJECTIVE: The sensitivity and specificity of the Chinese versions of the Hypomania Symptom Checklist-32 (HCL-32) and Mood Disorder Questionnaire (MDQ) for detecting bipolar disorder in Taiwan were explored in this study. METHODS: In total, 59 participants who were initially diagnosed with unipolar depression were recruited from an outpatient clinic and were screened for bipolar disorder using the HCL-32 and MDQ; each participant also underwent a diagnostic interview based on the Structured Clinical Interview for DSM-IV Axis disorder patients (SCID). RESULTS: The results showed that the HCL-32 yielded the best combination of sensitivity (100%) and specificity (46.2%) at a cut-off point of 7/8, and the MDQ yielded the best combination of sensitivity (71.4%) and specificity (76.9%) at a cut-off point of 6/7. CONCLUSION: The results of our study demonstrate that the HCL-32 and MDQ are of reasonable validity to distinguish between bipolar disorder and major depressive disorder. However small sample size may limit generalization of the results.

The interaction between BDNF and DRD2 in bipolar II disorder but not in bipolar I disorder.

Bipolar I (BP-I) and bipolar II (BP-II) disorders are the two most common subtypes of bipolar disorder. However, most studies have not differentiated bipolar disorder into BP-I and BP-II groups, for which the underlying etiology differentiating these two subtypes remains unclear. The genetic association between both subtypes is essential for improving our understanding. The dopamine D2 receptor/ankyrin repeat and kinase domain containing 1 (DRD2/ANKK1), one of the dopaminergic pathways, as well as the brain-derived neurotrophic factor (BDNF) gene, were reported as candidate genes in the etiology of bipolar disorder. Therefore, we examined the contribution of the BDNF and DRD2/ANKK1 genes and their interaction to the differentiation of BP-I and BP-II. Seven hundred ninety-two participants were recruited: 208 with BP-I, 329 with BP-II, and 255 healthy controls. The genotypes of the BDNF and DRD2/ANKK1 Taq1A polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis. A significant main effect for the Val/Val genotype of the BDNF Val66Met polymorphism predicted BP-II patients. The significant interaction effect for the Val/Val genotype of the BDNF Val66Met polymorphism and A1/A2 genotype of DRD2/ANKK1 Taq1A polymorphism was found only in BP-II patients. We provide initial evidence that the BDNF Val66Me and DRD2/ANKK1 Taq1A polymorphisms interact only in BP-II disorder and that BP-I and BP-II are genetically distinct.

Effects of C825T polymorphism of the GNB3 gene on availability of dopamine transporter in healthy volunteers--a SPECT study.

Striatal dopaminergic activity is significantly correlated with various cognitive activities, mood regulation, and even metabolic homeostasis, and is modulated by the dopamine transporter (DAT). The availability of DAT could be regulated by presynaptic autoreceptors, which are G-protein coupled receptors; however, whether functional variations in the common downstream signaling molecule, G-protein, could cause individual differences in presynaptic transporter availability remains unclear. To investigate this relationship, the DAT availability in seventy-eight healthy subjects was approximated using single photon emission computed tomography (SPECT) with [(99m)Tc] TRODAT-1, a radio-labeled form of tropan derivative for the selective labeling of DAT. The C825T single nucleotide polymorphism (SNP) (rs5443) of the beta subunit of the G-protein second messenger (GNß3) gene was genotyped, and analysis of variance showed a significant difference in striatal DAT when referenced to the entire occipital lobe among the three genotypes. Post hoc independent t tests were also performed, and showed that the striatal DAT availability of the CC genotype was higher than that of the other two genotypes. These results indicated that genetic variation in the common downstream signaling molecule of the dopamine autoreceptor could affect the functional status of the striatal dopamine system. These results together with the known role of the GNß3 gene might provide further evidence to support the common effect of the striatal dopamine system on mood and metabolic regulation.

No seasonal variation in human midbrain serotonin transporter availability in Taiwan.

Sunlight exposure is considered responsible for seasonal serotonin changes. Sixty-six healthy participants were recruited, and single photon emission computed tomography ([¹²³I]-ADAM SPECT) was used to investigate the association between serotonin transporter (SERT) availability and duration of sunlight exposure in Taiwan, a subtropical country. No significant correlation between SERT availability and the duration of sunlight exposure was found.

Is a patient-administered depression rating scale valid for detecting cognitive deficits in patients with major depressive disorder?

AIMS: Although cognitive deficits are a common and potentially debilitating feature of major depressive disorder (MDD), such subjective declines in cognitive function are seldom validated by objective methods as a clinical routine. The aim of this study was to validate the Taiwanese Depression Questionnaire (TDQ) for detecting cognitive deficits in a sample of drug-free patients with MDD. METHODS: The subjects consisted of 40 well-characterized medication-free patients with MDD and 40 healthy controls. Clinical and neuropsychological assessments, including the Wisconsin Card Sorting Test, the Wechsler Memory Scale-Revised, the Continuous Performance Test, and the Finger-Tapping Test, were administered at the time of recruitment. RESULTS: Factor analyses of the TDQ yielded three factors. Memory, attention and psychomotor performance were significantly poorer in patients with MDD. The performances of verbal and delayed memory of the Wechsler Memory Scale-Revised were correlated with the cognitive domains of the TDQ. Generalization of our results must be undertaken with caution considering the relatively small sample size, which could lead to increased ß-error. CONCLUSION: Cognitive subdomains might be considered important for including in patient-administered questionnaires used to measure symptoms of MDD when developing a new scale.

The ALDH2 and DRD2/ANKK1 genes interacted in bipolar II but not bipolar I disorder.

AIM: Clarifying the association between bipolar I and bipolar II, the two most common subtypes of bipolar disorder, at the genetic level is essential for improving our understanding of these disorders. The dopaminergic system has been implicated in the pathogenesis of bipolar disorder. It may be important to investigate genes involved in metabolizing dopamine and encoding dopamine receptors, such as the aldehyde dehydrogenase 2 (ALDH2) and dopamine D2 receptor/ankyrin repeat and kinase domain containing 1 (DRD2/ANKK1) genes. We examined the association of the ALDH2 and DRD2/ANKK1 Taq IA polymorphisms with bipolar I and II disorders and possible interactions between these genes. METHODS: Seven hundred and fifty participants were recruited: 207 with bipolar I disorder, 277 with bipolar II disorder, and 266 healthy controls. The genotypes of the ALDH2 and DRD2/ANKK1 TaqIA polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis. RESULTS: Logistic regression analysis showed a statistically significant interaction for the A1/A1 genotype of the DRD2/ANKK1 TaqIA, and the ALDH2*1*1 genotypes (P=0.009) could predict bipolar II patients compared with individuals without bipolar disorder. However, there was no association between the ALDH2 or DRD2/ANKK1 gene with neither bipolar I nor bipolar II disorder. CONCLUSION: Our findings may provide initial evidence that the ALDH2 and DRD2/ANKK1 genes interact in specific subtypes of bipolar disorders. Our findings also suggest a unique genetic distinction between bipolar I and bipolar II disorders.

Higher striatal dopamine transporters in euthymic patients with bipolar disorder: a SPECT study with [Tc] TRODAT-1.

OBJECTIVES: Dopamine has been implicated in the etiology of bipolar disorder. The aim of this study was to explore striatal dopamine transporter (DAT) availability in euthymic bipolar patients. METHODS: Seventeen drug-free euthymic bipolar patients were recruited. The availability of DAT was approximated using single photon emission computed tomography (SPECT) with [99mTc] TRODAT-1. RESULTS: Compared to the controls, the euthymic bipolar patients had significantly higher availability of striatal DAT. CONCLUSIONS: Even for patients in the euthymic state, the DAT availability is still higher than that of the controls.

Correlation between errors on the Wisconsin Card Sorting Test and the availability of striatal dopamine transporters in healthy volunteers.

BACKGROUND: Although studies have indicated that the frontal lobe plays an important role in performance on the Wisconsin Card Sorting Test (WCST) and that basal ganglia play a specific role in frontal lobe function, the role of striatal dopamine (DA) activity in performance on the WCST remains unclear. METHODS: We assessed the relation between the availability of striatal dopamine transporters (DATs) and performance on the WCST as a measure of executive function in healthy individuals. We approximated the availability of DATs in 53 healthy volunteers aged 19-61 years by use of single photon emission computed tomography with technetium-99m (99mTc)-TRODAT-1 as the ligand. The WCST was administered to all participants. RESULTS: The availability of DAT was significantly negatively correlated with perseverative errors on the WCST, both before and after adjustment for body mass index (r(before) = -0.39, p = 0.004; r(after) = -0.39, p = 0.005). LIMITATIONS: This was an association study; thus, a causal relation between DAT availability and performance cannot be confirmed. CONCLUSION: Our results suggest that striatal DAT availability may play a role in executive function as measured by the WCST.

MAOA interacts with the ALDH2 gene in anxiety-depression alcohol dependence.

BACKGROUND: Alcohol dependence is usually comorbid with anxiety disorder, depressive disorder, or both; this comorbidity may increase drinking behavior. We previously hypothesized that anxiety-depressive alcohol dependence (ANX/DEP ALC) was a genetically specific subtype of alcohol dependence. ANX/DEP ALC may be related to dopamine and serotonin, which are catalyzed by monoamine oxidase A (MAOA) and acetaldehyde dehydrogenase 2 (ALDH2). The aim of this study was to determine whether the interaction between the MAOA and the ALDH2 genes is associated with ANX/DEP ALC. METHODS: We recruited 383 Han Chinese men in Taiwan: 143 ANX/DEP ALC and 240 healthy controls. The diagnosis of ANX/DEP ALC (alcohol dependence with a past or current history of anxiety, depressive disorder, or both) was made using DSM-IV criteria. Genotypes of ALDH2 and MAOA-uVNTR (variable number of tandem repeat located upstream) were determined using PCR-RFLP. RESULTS: The ALDH2, but not the MAOA-uVNTR, polymorphism was associated with ANX/DEP ALC. After stratifying the MAOA-uVNTR polymorphism, we found a stronger association between the ALDH2*1/*2 and *2/*2 genotypes and the controls in the MAOA-uVNTR 4-repeat subgroup. Logistic regression significantly associated the interaction between ALDH2 and MAOA variants with ANX/DEP ALC. CONCLUSION: We conclude that the MAOA and ALDH2 genes interact in ANX/DEP ALC. Although the MAOA gene alone is not associated with ANX/DEP ALC, we hypothesize that different variants of MAOA-uVNTR polymorphisms modify the protective effects of the ALDH2*2 allele on ANX/DEP ALC in Han Chinese in Taiwan.