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A previous study indicated that mutations in the transmembrane protease serine 3 (TMPRSS3) gene, which encodes a transmembrane serine protease, cause nonsyndromic hearing loss (NSHL). This was the first description of a serine protease involved in hearing loss (HL). In Taiwan, however, data on the TMPRSS3 gene's association with NSHL is still insufficient. In this study, we described 10 mutations of TMPRSS3 genes found in 14 patients after screening 230 children with NSHL. The prevalence of the TMPRSS3 mutation appeared to be 6.09% (14/230). Of the 10 mutations, three were missense mutations: c.239G>A (p.R80H), c.551T>C (p.L184S), and 1253C>T (p.A418V); three were silent mutations, and four were mutations in introns. To determine the functional importance of TMPRSS3 mutations, we constructed plasmids carrying TMPRSS3 mutations of p.R80H, p.L184S, and p.A418V. TMPRSS3 function can be examined by secretory genetic assay for site-specific proteolysis (sGASP) and Xenopus oocyte expression system. Our results showed that p.R80H, p.L184S, and p.A418V TMPRSS3 mutations gave ratios of 19.4%, 13.2%, and 27.6%, respectively, via the sGASP system. Moreover, these three TMPRSS3 mutations failed to activate the epithelial sodium channel (ENaC) in the Xenopus oocyte expression system. These results indicate that the p.R80H, p.L184S, and p.A418V missense mutations of TMPRSS3 resulted in greatly diminishing the proteolytic activity of TMPRSS3. Our study provides information for understanding the importance of TMPRSS3 in the NSHL of Taiwanese children and provides a novel molecular explanation for the role of TMPRSS3 in HL., Competing Interests: The authors declare no conflict of interest. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors declare no conflict of interest.

Background: H. pylori CagL-Y58/E59 increase gastric cancer risk by stronger binding with integrin to faciliate type IV secretory system (T4SS). H. pylori can secrete high temperature requirement A (HtrA) to mediate E-Cadherin cleavage for gastric epithelial junction disruption, so H. pylori CagL can adhere to integrin located on basolateral side of epithelium. The study test whether H. pylori HtrA amino acid polymorphisms can increase gastric cancer risk synergistically with CagL-Y58/E59., Methods: One-hundred and sixty-four H. pylori-positive patients, including 71 with non-ulcer dyspepsia (NUD), 63 with peptic ulcers (PU), and 30 with gastric cancers (GC), were enrolled to receive upper gastrointestinal endoscopy to obtain gastric biopsies for H. pylori culture and histology by the updated Sydney system. Each isolate was screened for htrA & cagL genotype by polymerase chain reaction and HtrA & CagL-Y58/E59 amino acid sequence polymorphisms by sequencing., Results: The prevalence rates of htrA & cagL gene were both 100%. The HtrA amino acid sequence polymorphisms were not different between NUD and PU. The H. pylori isolates of GC had higher rates of HtrA residue 171 as leucine than those of NUD (73.3% vs. 50.7%, P = 0.036, OR[95%CI] = 2.7[1.1-6.8]). The risk of the H. pylori-infected subjects to get gastric cancer was increased up to 15.4-fold, if the infected isolates had presence of both HtrA-L171 and CagL-Y58/E59 (P < 0.001)., Conclusions: The H. pylori isolates of gastric cancer subjects had a higher rate of HtrA-L171. H. pylori isolates with presence of both HtrA-171 & CagL-Y58/E59 can synergistically increase the risk of gastric cancer.

The echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion gene is an important biomarker for target therapy. The aim of this study is to better understand the clinical and molecular features of the EML4-ALK fusion gene in lung cancer patients in Taiwan and therefore to generate an efficient algorithm for the detection of ALK translocation. In the first cohort, ALK translocation was identified in 1 adenocarcinoma from 100 lung cancer patients by using break apart fluorescent in situ hybridization (FISH). Next, we detected 6 ALK translocations in another 40 EGFR wild type adenocarcinomas but not in 40 cases with EGFR mutation. Histological analysis revealed that solid growth with signet-ring cells or cribriform glands with extracellular mucin were noted in all the 7 ALK translocated cases. One ALK positive cancer with mucinous cribriform pattern had no ALK expression. ALK expression was correlated with ALK translocation (p < 0.001), but not with ALK gene copy number gain (CNG) (P = 0.838). ALK translocation was also mutually exclusive with EGFR mutation in Taiwanese non-small cell lung cancer (P = 0.033). These results indicate that screening tests for EGFR mutation status and/or ALK expression could help efficiently select ALK translocated patients for target therapy., (© 2015 Japanese Society of Pathology and Wiley Publishing Asia Pty Ltd.)

Mutations in HTRA2 have been reported to associate with Parkinson's disease (PD). This study investigates if the genetic variants in HTRA2 contribute to Taiwanese PD. HTRA2 cDNA fragments from 80 patients with early-onset PD (onset ≤50 years) were sequenced. The identified variants were further examined for a cohort of PD and ethnically matched controls. A novel heterozygous R36W was identified in one early-onset and two late-onset PD patients, which was absent in 606 normal controls. The clinical features and 99mTc-TRODAT-1 SPECT image of the early-onset patient carrying R36W were similar to that of idiopathic PD. The R36W mutation of the patient was inherited from his mother whose SPECT revealed asymmetric reduction of 99mTc-TRODAT-1 uptake in the left striatum, suggesting that the defect of the nigrostriatal pathway may be attributable to the R36W in this family. Protein subcellular fractionation further revealed that R36W affected the processing of the proprotein after transport into mitochondria. Although the functional assays are promising, a larger cohort of both cases and controls should be screened to clarify the role of R36W in Taiwanese PD pathogenicity.

Background: An E670G polymorphism of the exon 12 of the proprotein convertase subtilisin/kexin type 9 (PCSK9) gene was recently found to be associated with increased plasma low-density lipoprotein cholesterol (LDL-C) levels and severity of coronary atherosclerosis. This case-control study tested for a possible link between this PCSK9 polymorphism and the risk of coronary artery disease (CAD) in an ethnic Chinese population in Taiwan., Methods: The subjects included 202 CAD patients and 614 unrelated controls. Genotypes were determined via polymerase chain reaction, restriction mapping with MboII, and gel electrophoresis., Results: Contradictory to the results of a previous report, a significantly lower level of LDL-C was noted in 670G carriers than in non-carriers (2.78+/-0.82 mmol/L vs. 3.02+/-0.85 mmol/L; p=0.029) among controls, after adjusting for age, gender, smoking, hypertension, diabetes mellitus, body mass index, and use of lipid-lowering agents. The 670G carrier was identified less frequently in patients with CAD than in controls (9.9% vs. 11.9%), but the difference was not significant in a multivariable logistic regression analysis (odds ratio=0.73; 95% CI=0.24-2.22; p=0.575). The G allele also occurred at similar frequencies in the two groups (5.0% vs. 6.0%; p=0.421)., Conclusions: These results indicate that the E670G polymorphism of the PCSK9 gene modulates plasma LDL-C levels, but that it is not a risk variant for CAD in ethnic Chinese in Taiwan.

Purpose: To investigate HTRA1 polymorphisms in unrelated Taiwan Chinese patients with age-related macular degeneration (AMD) and control subjects without AMD., Methods: A total of 95 unrelated Taiwan Chinese patients with AMD and 90 age- and sex-matched control subjects were enrolled in the study. Genomic DNA was prepared from peripheral blood obtained from all patients with AMD and control subjects. Polymerase chain reactions were used to analyze two HTRA1 single-nucleotide polymorphisms (rs11200638 [G/A] and rs10490924 [G/T])., Results: Of the 95 participants with AMD, dry AMD was diagnosed in 52 patients and wet AMD in 43 patients. Both rs11200638 (G/A) and rs10490924 (G/T) were significantly associated with all AMD (rs11200638: P = 6.7 x 10(-7) for an additive allele-dosage model, OR(het) = 1.97 [0.81, 4.81], OR(hom) = 8.59 [3.28, 22.49], A allele: 73% in all AMD versus 47% in controls; rs10490924: P = 9.2 x 10(-6), OR(het) = 1.86 [0.79, 4.35], OR(hom) = 5.08 [2.21, 11.70], T allele: 73% in all AMD versus 50% in controls). In terms of significance of association, rs11200638 was the most significantly associated variant. Subtype analysis including dry and wet AMD also revealed similar results. Haplotype analysis demonstrated that AT was significantly associated with wet and all AMD (P = 0.011 and 0.004, respectively), whereas GG was significantly associated with the control group when compared with all AMD (P = 0.035)., Conclusions: The study demonstrated that both single-nucleotide polymorphisms were significantly associated with dry and wet AMD and rs11200638 was the most significantly associated variant in a Taiwan Chinese population.

Reelin is an extracellular matrix glycoprotein that plays an important role in guiding neuronal migration, lamination and connection during embryonic brain development. Several reports suggest that reduced reelin expression is associated with human mental illnesses such as schizophrenia, mood disorders and autism. Human reelin cDNA has been cloned and contains a polymorphic GGC repeat at the 5' untranslated region. In view of the possible regulation of reelin gene expression by this GGC polymorphism, we investigated the association of the polymorphic GGC repeat with schizophrenia in a Chinese Han population from Taiwan. We found no differences of allelic and genotypic distributions of the polymorphic GGC triplets between 162 schizophrenic patients and 176 controls in this study. Our findings do not support the involvement of the polymorphic GGC triplets of the reelin gene in the pathogenesis of schizophrenia in the population studied.

Background: Previous studies presented the quasispecies spectrum of the envelope region of dengue virus type 3 (DENV-3) from either clinical specimens or field-caught mosquitoes. However, the extent of sequence variation among full genomic sequences of DENV within infected individuals remains largely unknown., Results: Instead of arbitrarily choosing one genomic region in this study, the full genomic consensus sequences of six DENV-3 isolates were used to locate four genomic regions that had a higher potential of sequence heterogeneity at capsid-premembrane (C-prM), envelope (E), nonstructural protein 3 (NS3), and NS5. The extent of sequence heterogeneity revealed by clonal sequencing was genomic region-dependent, whereas the NS3 and NS5 had lower sequence heterogeneity than C-prM and E. Interestingly, the Phylogenetic Analysis by Maximum Likelihood program (PAML) analysis supported that the domain III of E region, the most heterogeneous region analyzed, was under the influence of positive selection., Conclusion: This study confirmed previous reports that the most heterogeneous region of the dengue viral genome resided at the envelope region, of which the domain III was under positive selection pressure. Further studies will need to address the influence of these mutations on the overall fitness in different hosts (i.e., mosquito and human) during dengue viral transmission.