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Rotor syndrome is a rare, benign, inherited disorder that is commonly associated with mild hyperbilirubinemia. It is caused by bi-allelic pathological variants in both SLCO1B1 and SLCO1B3 genes, causing defective OATP1B1 and OATP1B3 in the sinusoidal membrane and interrupted bilirubin uptake of the hepatocytes. We report five Taiwanese pediatric and adult patients aged 5-32 years presenting with conjugated hyperbilirubinemia, and were found to have genetic variants of SLCO1B1 and SLCO1B3. Two also had history of prolonged neonatal jaundice. Genetic analysis using panel-based next generation sequencing revealed three patients with homozygous mutations c.1738C>T (p.R580∗) in SLCO1B1 and a transposon LINE-1 insertion in SLCO1B3, one patient with homozygous mutations for another haplotype, c.757C>T (p.R253∗) in SLCO1B1 and c.1747+1G>A in SLCO1B3. Another patient had heterozygous c.1738C>T (p.R580∗) in SLCO1B1 linked with a LINE-1 insertion in SLCO1B3, and heterozygous c.757C>T (p.R253∗) in SLCO1B1 linked with c.1747+1G>A in SLCO1B3. In conclusion, we present the first time of genetic diagnosis of Rotor syndrome in Taiwan. Advanced genetic testing has enhanced the diagnosis of rare diseases with mild symptoms., Competing Interests: Declaration of competing interest The authors have no conflicts of interest relevant to this article., (Copyright © 2023. Published by Elsevier B.V.)

Background: Thoracic aortic aneurysm and dissection (TAAD) is a devastating but treatable disease if detected early. The clinical manifestations and genetic characteristics underlying TAAD patients in Taiwan, however, remain unclear., Methods: We consecutively recruited patients referred for TAAD screening and/or management at a tertiary medical center in Taiwan. All patients received a comprehensive survey of the clinical manifestations and a genetic testing with a 29-gene next-generation sequencing (NGS) panel., Results: Patients (n = 107) were referred for different reasons, and could be grouped into 4 categories: known aortic aneurysm or dissection (AoAD) (n = 57), Marfanoid features (n = 36), having family members of suspected AoAD (n = 11), and ectopic lens (n = 3). AoAD were confirmed in 73 (68.2%) of the entire cohort. Among all the clinical manifestations, skin striae distensae was the only physical sign that showed significant association with AoAD (p = 0.007 after adjusted). Disease-causing genes/variants were identified in 46 patients (43.0%); FBN1 was the most prevalent disease-causing gene, followed by TGFBR1, TGFBR2 and FBN2. A positive genetic testing was not only an independent predictor of AoAD (hazard ratio (HR) 3.468, 95% confidence interval (CI) [1.541-7.807], p = 0.003), but also had a higher chance of dissection among the patients with known dilated aorta (HR 4.552, 95% CI [1.578-13.135], p = 0.005)., Conclusion: The presence of skin striae distensae may serve as a clinical cue for physicians to search for AoAD in subjects who are at risk. The NGS panel test not only helps confirm the diagnosis, but also stratify the risk of dissection among patients with dilated aorta., Competing Interests: Declaration of competing interest The authors have no conflicts of interest relevant to this article., (Copyright © 2021 Formosan Medical Association. Published by Elsevier B.V. All rights reserved.)

Background/purpose: A heterozygous three-nucleotide (GAG) in-frame deletion in the TOR1A gene causes the rare disease, dystonia (DYT1), which typically presents as focal limb dystonia during adolescence, then spreads to other limbs. This study investigated the frequency and clinical features of DYT1 in a Taiwanese dystonia cohort., Methods: We performed targeted next generation sequencing in 318 patients with primary dystonia. We identified one DYT1 family with various types of dystonia, and we described the clinical presentations observed in this family during a 30-year follow-up. We compared the clinical characteristics to those reported in previous studies on DYT1 from 2000 to 2020., Results: Among 318 patients, we identified only one DYT1 patient (0.3%) with an autosomal dominant family history of dystonia. The proband was a 43-year-old man that experienced progressive onset of focal lower limb dystonia from age 11 years. The disease spread caudal-rostrally to the upper limbs and cervical muscles. Prominent cervical dystonia was noted during follow-up, which was an atypical presentation of DYT1. Clinical assessments of other family members showed intrafamily variability. The proband's father and an affected sibling demonstrated only mild right-hand writer's cramp. A systematic review of previously reported DTY1 cases showed that Asian patients had a higher frequency of cervical dystonia (44.8%) than groups of Ashkenazi Jews (35%) and Non-Jewish Caucasians (30.5%) (P = 0.04)., Conclusion: Our findings revealed that DYT1 is rare in a Taiwanese dystonia cohort. The presentation of marked cervical dystonia could be the main feature of Asian patients with DYT1., Competing Interests: Declaration of competing interest The authors have no conflicts of interest relevant to this article., (Copyright © 2021 Formosan Medical Association. Published by Elsevier B.V. All rights reserved.)

Background/purpose: Malignant hyperthermia (MH) is a life-threatening pharmacogenetic disease with only two known causative genes, RYR1 and CACNA1S. Both are huge genes containing numerous exons, and they reportedly only account for 50-70% of known MH patients. Next-generation sequencing (NGS) technology and bioinformatics could help delineate the genetic diagnosis of MH and several MH-like clinical presentations., Methods: We established a capture-based targeted NGS sequencing framework to examine the whole genomic regions of RYR1, CACNA1S and the 16.6 Kb mitochondrial genome, as well as 12 other genes related to excitation-contraction coupling and/or skeletal muscle calcium homeostasis. We applied bioinformatics analyses to the variants identified in this study and also to the 48 documented RYR1 pathogenic variants., Results: The causative variants were identified in seven of the eight (87.5%) MH families, but in none of the 10 individuals classified as either normal controls (N = 2) or patients displaying MH-like clinical features later found to be caused by other etiologies (N = 8). We showed that RYR1 c.1565A>G (p.Tyr522Cys)(rs118192162) could be a genetic hot spot in the Taiwanese population. Bioinformatics analyses demonstrated low population frequencies and predicted damaging effects from all known pathogenic RYR1 variants. We estimated that more than one in 1149 individuals worldwide carry MH pathogenic variants at RYR1., Conclusion: NGS and bioinformatics are sensitive and specific tools to examine RYR1 and CACNA1S for the genetic diagnosis of MH. Pathogenic variants in RYR1 can be found in the majority of MH patients in Taiwan., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest relevant to this article., (Copyright © 2020. Published by Elsevier B.V.)

Background/purpose: Genetic variant of HSD3B1 1245 is known to augment androgen production at peripheral tissue as skin. This study aimed to investigate whether women with polycystic ovary syndrome inheriting this variant exhibit specific androgenic phenotypes., Methods: A cross-sectional study of Taiwanese women with polycystic ovary syndrome, defined by Rotterdam criteria, at the reproductive endocrinology outpatient clinic in a university affiliated hospital., Results: The presence of female pattern hair loss in women with polycystic ovary syndrome was significantly associated with an increased body mass index, decreased sex hormone binding globulin and high density lipoprotein cholesterol levels, elevated triglyceride levels, and increased prevalence of hypertension. Using stepwise multivariate logistic regression analysis, body mass index, triglyceride and HSD3B1 1245 AC or CC genotype were significantly related to female pattern hair loss in women with polycystic ovary syndrome after considering other variables. Overweight women with polycystic ovary syndrome had significantly higher risk of female pattern hair loss than normal-weight women with polycystic ovary syndrome. The presence of female pattern hair loss was higher in overweight women with polycystic ovary syndrome who comprised HSD3B1 AC or CC genotype compared with wild type., Conclusion: Carrying the HSD3B1 1245C allele and overweight are associated with the presence of female pattern hair loss in women with polycystic ovary syndrome., (Copyright © 2019 Formosan Medical Association. Published by Elsevier B.V. All rights reserved.)

Background/purpose: Surgery followed by radioiodine is a mainstay of treatment for thyroid cancers of follicular origins. However, about 5% of the thyroid cancers are non-operable and/or radioiodine-refractory diseases, which are either locally advanced or metastatic and result in a survival of less than 5 years. How to treat this population of thyroid cancer patients becomes a critical issue requiring further understanding of the tumor's genetic information., Methods: We used formalin-fixed paraffin-embedded specimens of 22 fatal thyroid cancers and their corresponding non-tumor parts, if available, to yield genomic DNA, and applied the Ion Torrent™ Personal Genome Machine (IT-PGM) System (Life Technologies), a next generation sequencing technology, to interrogate 740 mutational hotspots in 46 oncogenes. We further validated the results by conventional direct sequencing., Results: We confirmed 21 mutations of 11 oncogenes in the 22 fatal thyroid cancer samples. Among them, the MET p.N375S and MLH1 p.V384D mutations, each was detected in two cases, and has rarely been found to be involved in thyroid cancer pathogenesis before. We also identified homozygous PDGFRA p.V824V mutation in eight out of the 22 cases, while the non-tumor counterparts carried heterozygous PDGFRA p.V824V mutation. We noted that the Ion Torrent technique unfortunately showed high false positive rates for detecting EGFR mutations in thyroid cancers., Conclusion: The extensive genetic studies provide new insights to future targeted therapy in these patients. IT-PGM proved to be valuable for comprehensively searching genetic mutations in potentially fatal thyroid cancers., (Copyright © 2017. Published by Elsevier B.V.)

Isodicentric X chromosomes in general have phenotypes characteristic of the resultant X deletions. Gonadotropin levels in Turner's syndrome (TS) girls are high, but have a normal biphasic pattern. Here, we report a 21-year-old lady with primary amenorrhea. Clinical examination revealed a short neck but no other typical stigmata of Turner's syndrome. The levels of gonadotropin were not raised to post-menopausal levels. A chromosome study showed a 45,X/46,X,idic(X)(q22) karyotype. She was diagnosed as having Turner's syndrome., (Copyright © 2012. Published by Elsevier B.V.)