A splicing-regulatory polymorphism in DRD2 disrupts ZRANB2 binding, impairs cognitive functioning and increases risk for schizophrenia in six Han Chinese samples.

The rs1076560 polymorphism of DRD2 (encoding dopamine receptor D2) is associated with alternative splicing and cognitive functioning; however, a mechanistic relationship to schizophrenia has not been shown. Here, we demonstrate that rs1076560(T) imparts a small but reliable risk for schizophrenia in a sample of 616 affected families and five independent replication samples totaling 4017 affected and 4704 unaffected individuals (odds ratio=1.1; P=0.004). rs1076560(T) was associated with impaired verbal fluency and comprehension in schizophrenia but improved performance among healthy comparison subjects. rs1076560(T) also associated with lower D2 short isoform expression in postmortem brain. rs1076560(T) disrupted a binding site for the splicing factor ZRANB2, diminished binding affinity between DRD2 pre-mRNA and ZRANB2 and abolished the ability of ZRANB2 to modulate short:long isoform-expression ratios of DRD2 minigenes in cell culture. Collectively, this work implicates rs1076560(T) as one possible risk factor for schizophrenia in the Han Chinese population, and suggests molecular mechanisms by which it may exert such influence.

A genome-wide search for chromosomal loci linked to bipolar affective disorder in the Old Order Amish.

The most characteristic features of bipolar affective disorder (manic-depressive illness) are episodes of mania (bipolar I, BPI) or hypomania (bipolar II, BPII) interspersed with periods of depression. Manic-depressive illness afflicts about one percent of the population, and if untreated, is associated with an approximately 20% risk of suicide. Twin, family and adoption studies provide compelling evidence for a partial genetic aetiology, but the mode(s) of inheritance has not been identified. Nonetheless, the majority of genetic linkage studies have assumed classical mendelian inheritance attributable to a single major gene. Although segregation analyses have yielded inconsistent results (with most studies rejecting a single locus inheritance model), the best single gene model is dominant inheritance if only BPI is considered. Reported linkages of bipolar affective disorder on chromosomes 11, 18, 21 and X have been difficult to substantiate, and additional studies are required for replication or exclusion of these regions. We now present the results of our genome-wide linkage analyses that provide evidence that regions on chromosomes 6, 13 and 15 harbour susceptibility loci for bipolar affective disorder, suggesting that bipolar affective disorder in the Old Order Amish is inherited as a complex trait.

Genome-wide association study of bipolar I disorder in the Han Chinese population.

We report the first genome-wide association study in 1000 bipolar I patients and 1000 controls, with a replication of the top hits in another 409 cases and 1000 controls in the Han Chinese population. Four regions with most strongly associated single-nucleotide polymorphisms (SNPs) were detected, of which three were not found in previous GWA studies in the Caucasian populations. Among them, SNPs close to specificity protein 8 (SP8) and ST8 α-N-acetyl- neuraminide α-2,8-sialyltransferase (ST8SIA2) are associated with Bipolar I, with P-values of 4.87 × 10(-7) (rs2709736) and 6.05 × 10(-6) (rs8040009), respectively. We have also identified SNPs in potassium channel tetramerization domain containing 12 gene (KCTD12) (rs2073831, P=9.74 × 10(-6)) and in CACNB2 (Calcium channel, voltage-dependent, ß-2 subunit) gene (rs11013860, P=5.15 × 10(-5)), One SNP nearby the rs1938526 SNP of ANK3 gene and another SNP nearby the SNP rs11720452 in chromosome 3 reported in previous GWA studies also showed suggestive association in this study (P=6.55 × 10(-5) and P=1.48 × 10(-5), respectively). This may suggest that there are common and population-specific susceptibility genes for bipolar I disorder.

A genome-wide association study identifies new loci for ACE activity: potential implications for response to ACE inhibitor.

Because angiotensin-converting enzyme (ACE) activity is implicated widely in biological systems, we aimed to identify its novel quantitative trait loci for the purposes of understanding ACE activity regulation and pharmacogenetics relating to ACE inhibitor (ACEI). We performed a two-stage genome-wide association study: (1) from 400 young-onset hypertension (YOH) subjects and (2) a confirmation study with an additional 623 YOH subjects. In the first stage, eight single nucleotide polymorphisms (SNPs) of the ACE structural gene and one SNP of ABO genes were significantly associated with ACE activity. SNP rs4343 in exon17 near the well-known insertion/deletion polymorphism had the strongest association. We confirmed in the second stage that three SNPs: rs4343 in ACE gene (P=3.0 x 10⁻²5), rs495828 (P=3.5 x 10⁻8) and rs8176746 (P=9.3 x 10⁻5) in ABO gene were significantly associated with ACE activity. We further replicated the association between ABO genotype/blood types and ACE activity in an independent YOH family study (428 hypertension pedigrees), and showed a potential differential blood pressure response to ACEI in subjects with varied numbers of ACE-activity-raising alleles. These findings may broaden our understanding of the mechanisms controlling ACE activity and advance our pharmacogenetic knowledge on ACEI.

Family-based association study of cytotoxic T-lymphocyte antigen-4 with susceptibility to Graves' disease in Han population of Taiwan.

Graves' disease (GD) is a common organ-specific autoimmune disorder inherited as a complex trait. Although there has not been consensus regarding the genuine susceptibility alleles, many population-based genetic studies showed association of the cytotoxic T-lymphocyte antigen-4 (CTLA4) gene with GD. In contrast, evidence utilizing family-based studies came only from the Caucasian population. Here we performed a family-based association study in the Han population in Taiwan. We enrolled 374 affected individuals and 347 unaffected family members in 151 GD pedigrees. Four single-nucleotide polymorphisms (SNP) and a short tandem repeat polymorphism (STRP) at CTLA4 were genotyped. Association of GD with a novel risk SNP at the 5' upstream region, CTLA4_-1722_T/C (rs733618), was demonstrated (P=0.0096). We also replicated the association signal of a coding SNP, CTLA4_+49_G/A (rs231775, P=0.0219). A common haplotype composed of CTLA4_-1722_T/C and CTLA4_(AT)n (an STRP marker: UniSTS:48500) showed protective effect (P=0.0004). Our results of family-based association study, taken together with those from the Caucasian population, provide evidence that CTLA4 confers susceptibility to GD across different ethnic backgrounds.

A genome-wide study of preferential amplification/hybridization in microarray-based pooled DNA experiments.

Microarray-based pooled DNA methods overcome the cost bottleneck of simultaneously genotyping more than 100 000 markers for numerous study individuals. The success of such methods relies on the proper adjustment of preferential amplification/hybridization to ensure accurate and reliable allele frequency estimation. We performed a hybridization-based genome-wide single nucleotide polymorphisms (SNPs) genotyping analysis to dissect preferential amplification/hybridization. The majority of SNPs had less than 2-fold signal amplification or suppression, and the lognormal distributions adequately modeled preferential amplification/hybridization across the human genome. Comparative analyses suggested that the distributions of preferential amplification/hybridization differed among genotypes and the GC content. Patterns among different ethnic populations were similar; nevertheless, there were striking differences for a small proportion of SNPs, and a slight ethnic heterogeneity was observed. To fulfill appropriate and gratuitous adjustments, databases of preferential amplification/hybridization for African Americans, Caucasians and Asians were constructed based on the Affymetrix GeneChip Human Mapping 100 K Set. The robustness of allele frequency estimation using this database was validated by a pooled DNA experiment. This study provides a genome-wide investigation of preferential amplification/hybridization and suggests guidance for the reliable use of the database. Our results constitute an objective foundation for theoretical development of preferential amplification/hybridization and provide important information for future pooled DNA analyses.

Association evidence of schizophrenia with distal genomic region of NOTCH4 in Taiwanese families.

Evidence for association with schizophrenia has been reported for NOTCH4, although results have been inconsistent. Previous studies have focused on polymorphisms in the 5' promoter region and first exon of NOTCH4. Our aim was to test the association of the entire genomic region of NOTCH4 in 218 families with at least two siblings affected by schizophrenia in Taiwan. We genotyped seven single nucleotide polymorphisms (SNPs) of this gene, with average intermarker distances of 5.3 kb. Intermarker linkage disequilibrium (LD) was calculated using gold software, and single-locus and haplotype association analyses were performed using transmit software. We found that the T allele of SNP rs2071285 (P= 0.035) and the G allele of SNP rs204993 (P= 0.0097) were significantly preferentially transmitted to the affected individuals in the single-locus association analysis. The two SNPs were in high LD (D' > 0.8). Trend for overtransmission was shown for the T-G haplotype of the two SNPs to affected individuals (P= 0.053), with the A-A haplotype significantly undertransmitted (P= 0.034). The associated region distributed across the distal portion of the NOTCH4 gene and overlapped with the genomic region of the G-protein signaling modulator 3 and pre-B-cell leukemia transcription factor 2. In summary, we found modest association evidence between schizophrenia and the distal genomic region of NOTCH4 in this Taiwanese family sample. Further replication for association with the distal genomic region of NOTCH4 is warranted.

Meta-analysis of effectiveness and safety of abciximab versus eptifibatide or tirofiban in percutaneous coronary intervention.

Three platelet glycoprotein (GP) IIb/IIIa receptor antagonists have been evaluated in patients undergoing percutaneous coronary intervention (PCI). One of these agents, abciximab, is structurally and pharmacologically quite different from the other 2, eptifibatide and tirofiban. We conducted a meta-analysis to determine whether different antagonist types achieved different clinical outcomes, possibly related to their structural differences. Odds ratios (OR) were calculated and a random effects model was used to combine the outcomes of 14,644 patients enrolled in 8 prospective, randomized, placebo-controlled clinical trials assessing treatment with a GP IIb/IIIa inhibitor to prevent ischemic complications of PCI. Neither abciximab (OR 0.69; 95% confidence interval [CI] 0.4 to 1.9) nor eptifibatide or tirofiban treatment (OR 0.74; 95% CI 0.4 to 1.28) resulted in reductions in mortality. Only the abciximab-treated patients had reductions in myocardial infarction (4.3% vs 8.5%, OR 0.49; 95% CI 0.40 to 0.59). There was no effect of eptifibatide or tirofiban on myocardial infarction (OR 0.85; 95% CI 0.69 to 1.04). Urgent revascularization was reduced in both abciximab-treated (2.7% vs 6.2%, OR 0.42; 95% CI 0.34 to 0.53) and eptifibatide- and tirofiban-treated (4.2% vs 5.5%, OR 0.76; 95% CI 0.60 to 0.96) groups. Only abciximab-treated patients had increased major bleeding (5.8% vs 3.8%; OR 1.53; 95% CI 1.24 to 1.90). There was no effect of eptifibatide or tirofiban on major bleeding (5.0% vs 4.3%; OR 1.19; 95% CI 0.94 to 1.52). Thus, significant differences exist between clinical outcomes achieved by abciximab and those achieved by eptifibatide or tirofiban following PCl procedures.

Suggestive evidence for linkage of schizophrenia to markers at chromosome 15q13-14 in Taiwanese families.

In order to evaluate the linkage of schizophrenia to loci at chromosome 15q, we genotyped six microsatellite markers at chromosome 15q11-14 in 52 Taiwanese schizophrenic families. Two phenotype models (narrow: DSM-IV schizophrenia only; and broad: including schizophrenia, schizoaffective, and other nonaffective psychotic disorders) were used to define the disease phenotype. Maximum nonparametric linkage scores (NPL scores) of 3.33 (P = 0.0003) and 2.96 (P = 0.0008) were obtained at the marker D15S976 under broad and narrow models, respectively. Positive linkage results were also observed at the marker D15S1360, previously reported to have significant linkage to a neurophysiological deficit of schizophrenia, with NPL scores of 2.71 (P = 0.003) and 2.78 (P = 0.002) under broad and narrow models, respectively. The results provide suggestive linkage evidence of schizophrenia to loci at chromosome 15q13-14 in an ethnically distinct Taiwanese sample.

Comparison of postmortem techniques for the detection of Mycobacterium bovis in white-tailed deer (Odocoileus virginianus).

A retrospective study of various diagnostic postmortem techniques used in a 4-year surveillance program for detection of Mycobacterium bovis infection in wild white-tailed deer (Odocoileus virginianus) was conducted. The tests evaluated were routine histopathology, acid-fast staining, detection of acid-fast bacilli in culture, and an M. tuberculosis group-specific genetic probe applied to pure cultures. Each of these techniques were compared with a reference or "gold standard" of mycobacterial culture and identification. Histopathology, the most rapid form of testing for M. bovis infection in white-tailed deer samples, had a sensitivity of 98% and a specificity of 87%, resulting in a positive predictive value of 94%. The detection of acid-fast bacilli by staining was less sensitive than histopathology (90%), but its higher specificity (97%) resulted in a positive predictive value of 99%. The detection of acid-fast bacilli on culture was both highly specific (93%) and sensitive (100%). The group-specific genetic probe had the highest sensitivity and specificity and produced results in complete agreement with those of mycobacterial culture, suggesting that this technique could be used as the new "gold standard" for this particular wildlife tuberculosis surveillance program.

Mycobacterium bovis in coyotes from Michigan.

During a survey for tuberculosis in wild carnivores and omnivores, Mycobacterium bovis was cultured from pooled lymph nodes of three adult female coyotes (Canis latrans) harvested by hunters in Michigan (USA). No gross or histologic lesions suggestive of tuberculosis were seen in these animals. One coyote was taken from Montmorency county and two coyotes from Alcona county located in the north-eastern portion of Michigan's Lower Peninsula where free-ranging white-tailed deer (Odocoileus virginianus) have been found infected with bovine tuberculosis. It is thought that these coyotes became infected with M. bovis through the consumption of tuberculous deer. Other species included in the survey were the opossum (Didelphis virginiana), raccoon (Procyon lotor), red fox (Vulpes vulpes), bobcat (Felis rufus), and badger (Taxidea taxus).

Bovine tuberculosis in free-ranging white-tailed deer from Michigan.

A 4.5 yr-old male white-tailed deer (Odocoileus virginianus) killed by a hunter during the 1994 firearm hunting season in northeastern Michigan (USA) had lesions suggestive of tuberculosis and was positive on culture for Mycobacterium bovis the causative agent for bovine tuberculosis. Subsequently, a survey of 354 hunter-harvested white-tailed deer for tuberculosis was conducted in this area from 15 November 1995 through 5 January 1996. Heads and/or lungs from deer were examined grossly and microscopically for lesions suggestive of bovine tuberculosis. Gross lesions suggestive of tuberculosis were seen in 15 deer. Tissues from 16 deer had acid-fast bacilli on histological examination and in 12 cases mycobacterial isolates from lymph nodes and/or lungs were identified as M. bovis. In addition, lymph nodes from 12 deer (11 females and 1 male) without gross or microscopic lesions were pooled into 1 sample from which M. bovis was cultured. Although more male (9) than female (3) deer had bovine tuberculosis infections, this difference was not statistically significant. Mycobacterium bovis culture positive deer ranged in age from 1.5 to 5.5 yr with a mean of 2.7 yr (median 2.5 yr) for males and 3.2 yr (median 3.5 yr) for females. This appears to be the first epidemic occurrence of M. bovis in free-ranging cervids in North America. A combination of environmental (high deer density and poor quality habit) and management-related factors (extensive supplemental feeding) may be responsible for this epizootic.

Bovine tuberculosis in free-ranging carnivores from Michigan.

During a survey of carnivores and omnivores for bovine tuberculosis conducted in Michigan (USA) since 1996, Mycobacterium bovis was cultured from lymph nodes pooled from six coyotes (Canis latrans) (four adult female, two adult male), two adult male raccoons (Procyon lotor), one adult male red fox (Vulpes vulpes), and one 1.5-yr-old male black bear (Ursus americanus). One adult, male bobcat (Felis rufus) with histologic lesions suggestive of tuberculosis was negative on culture but positive for organisms belonging to the Mycobacterium tuberculosis complex when tested by polymerase chain reaction. All the tuberculous animals were taken from three adjoining counties where M. bovis is known to be endemic in the free-ranging white-tailed deer (Odocoileus virginianus) population. There were two coyotes, one raccoon, one red fox, and one bobcat infected in Alpena county. Montmorency County had two coyotes and one raccoon with M. bovis. Two coyotes and a bear were infected from Alcona County. These free-ranging carnivores/omnivores probably became infected with M. bovis through consumption of tuberculous deer. Other species included in the survey were opossum (Didelphis virginiana), gray fox (Urocyon cinereoargenteus), and badger (Taxidea taxus); these were negative for M. bovis.

Naturally occurring tuberculosis in white-tailed deer.

OBJECTIVE: To determine the distribution of lesions and extent of tissues infected with Mycobacterium bovis in a captive population of white-tailed deer. DESIGN: Cross-sectional study. ANIMALS: 116 captive white-tailed deer. PROCEDURE: Deer were euthanatized, and postmortem examinations were performed. Tissues with gross lesions suggestive of tuberculosis were collected for microscopic analysis and bacteriologic culture. Tissues from the head, thorax, and abdomen of deer with no gross lesions were pooled for bacteriologic culture. Tonsillar, nasal, oral, and rectal swab specimens, fecal samples, and samples of hay and pelleted feed, soil around feeding sites, and water from 2 natural ponds were collected for bacteriologic culture. RESULTS: Mycobacterium bovis was isolated from 14 of 116 (12%) deer; however, only 9 of 14 had lesions consistent with tuberculosis. Most commonly affected tissues included the medial retropharyngeal lymph node and lung. Five of 14 tuberculous deer had no gross lesions; however, M bovis was isolated from pooled tissue specimens from the heads of each of these deer. Bacteriologic culture of tonsillar swab specimens from 2 of the infected deer yielded M bovis. Mean (+/- SEM) age of tuberculous deer was 2.5 +/- 0.3 years (range, 0.5 to 6 years). Mycobacterium bovis was not isolated from feed, soil, water, or fecal samples. CONCLUSIONS AND CLINICAL RELEVANCE: Examination of hunter-killed white-tailed deer for tuberculosis commonly includes only the lymph nodes of the head. Results of such examinations may underestimate disease prevalence by as much as 57%. Such discrepancy should be considered when estimating disease prevalence.

Genetic polymorphisms and tissue expression of interleukin-22 associated with risk and therapeutic response of gastric mucosa-associated lymphoid tissue lymphoma.

Chronic Helicobacter pylori-stimulated immune reactions determine the pathogenesis of gastric mucosa-associated lymphoid tissue (MALT) lymphoma. We aimed to explore the genetic predisposition to this lymphoma and its clinical implication. A total of 68 patients and 140 unrelated controls were genotyped for 84 single-nucleotide polymorphisms in genes encoding cytokines, chemokines and related receptors that play important roles in T cell-mediated gastrointestinal immunity. Five genotypes in IL-22, namely CC at rs1179246, CC at rs2227485, AA at rs4913428, AA at rs1026788 and TT at rs7314777, were associated with disease susceptibility. The former four genotypes resided in the same linkage disequilibrium block (r(2)=0.99) that conferred an approximately threefold higher risk. In vitro experiments demonstrated that co-culturing peripheral mononuclear cells or CD4(+) T cells with H. pylori stimulated the secretion of interleukin-22 (IL-22), and that IL-22 induced the expression of antimicrobial proteins, RegIIIα and lipocalin-2, in gastric epithelial cells. Furthermore, patients with gastric tissue expressing IL-22 were more likely to respond to H. pylori eradication (14/22 vs 4/19, P<0.006). We conclude that susceptibility of gastric MALT lymphoma is influenced by genetic polymorphisms in IL-22, the product of which is involved in mucosal immunity against H. pylori and associated with tumor response to H. pylori eradication.