Quantitative DNA Methylation Analysis and Epigenotype-Phenotype Correlations in Taiwanese Patients with Silver-Russell Syndrome.

Background: Silver-Russell syndrome (SRS; OMIM #180860) is a clinically and genetically heterogeneous imprinting disorder characterized by prenatal and postnatal growth failure. The aim of this study was to identify the epigenotype-phenotype correlations in these patients using quantitative DNA methylation analysis. Methods: One hundred and eighty-three subjects clinically suspected of having SRS were referred for diagnostic testing by the methylation profiling of H19-associated imprinting center (IC) 1 and imprinted PEG1/MEST regions using methylation-specific high-resolution melting analysis and methylation quantification with the MassARRAY assay. Correlations between quantitative DNA methylation status and clinical manifestations of the subjects according to the Netchine-Harbison (N-H) clinical scoring system for SRS were analyzed. Results: Among the 183 subjects, 90 had a clinical diagnosis of SRS [N-H score ≥ 4 (maximum = 6)] and 93 had an SRS score < 4. Molecular lesions were detected in 41% (37/90) of the subjects with a clinical diagnosis of SRS, compared with 3% (3/93) of those with an N-H score < 4. The IC1 methylation level was negatively correlated with the N-H score. The molecular diagnosis rate was positively correlated with the N-H score. Thirty-one subjects had IC1 hypomethylation (IC1 methylation level <35% by the MassARRAY assay), seven had maternal uniparental disomy 7, and two had pathogenic copy number variants. Among the 90 subjects with an N-H score ≥ 4, the IC1 methylation level was significantly different between those with or without some clinical SRS features, including birth length ≤ 10th centile, relative macrocephaly at birth, normal cognitive development, body asymmetry, clinodactyly of the fifth finger, and genital abnormalities. Conclusions: This study confirmed the suitability of the N-H clinical scoring system as clinical diagnostic criteria for SRS. Quantitative DNA methylation analysis using the MassARRAY assay can improve the detection of epigenotype-phenotype correlations, further promoting better genetic counseling and multidisciplinary management for these patients.

Is Non-Stimulated C-Peptide at Diagnosis a Good Predictive Value for Insulin Use at Two Years after Diagnosis in Pediatric Diabetic Patients?

Background and Objectives: Insulin treatment may be initially required to stabilize patients presenting with metabolic crisis at type 1 and 2 diabetes mellitus (DM) onset. Some patients with type 2 DM may need persistent insulin treatment. This study aimed to examine the predictive performance of non-stimulated C-peptide level at the time of diagnosis for future insulin use in pediatric diabetic patients. Materials and Methods: We reviewed the medical charts of diabetic patients aged 18 years or younger in a medical center in southern Taiwan from January 2000 to December 2019. Clinical and individual data were collected at the time of DM diagnosis. Outcomes were persistent insulin use at the time of diagnosis, as well as at one and two years after diagnosis. Results: The final analysis included a total of 250 patients. The best cut-off point of non-stimulated C-peptide was 0.95 ng/mL, and the predictive indices for the insulin use were 0.84 for sensitivity and 0.94 for specificity at two years after DM diagnosis. Incorporating age at onset and presence of GAD antibodies can further increase the predictive power of non-stimulated C-peptide. Conclusions: The value of non-stimulated C-peptide at diabetic onset was feasible and effective for predicting future insulin treatment up to the time point of two years after diagnosis.

Identification of southern Taiwan genetic variants in thyroid dyshormonogenesis through whole-exome sequencing.

Thyroid dyshormonogenesis (TDH) is responsible for 15%-25% of congenital hypothyroidism (CH) cases. Pathogenetic variants of this common inherited endocrine disorders vary geographically. Unraveling the genetic underpinnings of TDH is essential for genetic counseling and precise therapeutic strategies. This study aims to identify genetic variants associated with TDH in Southern Taiwan using whole exome sequencing (WES). We included CH patients diagnosed through newborn screening at a tertiary medical center from 2011 to 2022. Permanent TDH was determined based on imaging evidence of bilateral thyroid structure and the requirement for continuous medication beyond 3 years of age. Genomic DNA extracted from blood was used for exome library construction, and pathogenic variants were detected using an in-house algorithm. Of the 876 CH patients reviewed, 121 were classified as permanent, with 47 (40%) confirmed as TDH. WES was conducted for 45 patients, and causative variants were identified in 32 patients (71.1%), including DUOX2 (15 cases), TG (8 cases), TSHR (7 cases), TPO (5 cases), and DUOXA2 (1 case). Recurrent variants included DUOX2 c.3329G>A, TSHR c.1349G>A, TG c.1348delT, and TPO c.2268dupT. We identified four novel variants based on genotype, including TSHR c.1135C>T, TSHR c.1349G>C, TG c.2461delA, and TG c.2459T>A. This study underscores the efficacy of WES in providing definitive molecular diagnoses for TDH. Molecular diagnoses are instrumental in genetic counseling, formulating treatment, and developing management strategies. Future research integrating larger population cohorts is vital to further elucidate the genetic landscape of TDH.

Syndromic ciliopathy: a taiwanese single-center study.

BACKGROUND: Syndromic ciliopathies are a group of congenital disorders characterized by broad clinical and genetic overlap, including obesity, visual problems, skeletal anomalies, mental retardation, and renal diseases. The hallmark of the pathophysiology among these disorders is defective ciliary functions or formation. Many different genes have been implicated in the pathogenesis of these diseases, but some patients still remain unclear about their genotypes. METHODS: The aim of this study was to identify the genetic causes in patients with syndromic ciliopathy. Patients suspected of or meeting clinical diagnostic criteria for any type of syndromic ciliopathy were recruited at a single diagnostic medical center in Southern Taiwan. Whole exome sequencing (WES) was employed to identify their genotypes and elucidate the mutation spectrum in Taiwanese patients with syndromic ciliopathy. Clinical information was collected at the time of patient enrollment. RESULTS: A total of 14 cases were molecularly diagnosed with syndromic ciliopathy. Among these cases, 10 had Bardet-Biedl syndrome (BBS), comprising eight BBS2 patients and two BBS7 patients. Additionally, two cases were diagnosed with Alström syndrome, one with Oral-facial-digital syndrome type 14, and another with Joubert syndrome type 10. A total of 4 novel variants were identified. A recurrent splice site mutation, BBS2: c.534 + 1G > T, was present in all eight BBS2 patients, suggesting a founder effect. One BBS2 patient with homozygous c.534 + 1G > T mutations carried a third ciliopathic allele, TTC21B: c.264_267dupTAGA, a nonsense mutation resulting in a premature stop codon and protein truncation. CONCLUSIONS: Whole exome sequencing (WES) assists in identifying molecular pathogenic variants in ciliopathic patients, as well as the genetic hotspot mutations in specific populations. It should be considered as the first-line genetic testing for heterogeneous disorders characterized by the involvement of multiple genes and diverse clinical manifestations.

HNRNPC mediates lymphatic metastasis of cervical cancer through m6A-dependent alternative splicing of FOXM1.

Cervical cancer (CCa) patients with lymph node (LN) metastasis face poor prognoses and have limited treatment options. Aberrant N6-methyladenosine (m6A) modification of RNAs are known to promote tumor metastasis, but their role in CCa remains unclear. Our study reveals that HNRNPC, an alternative splicing (AS) factor and m6A reader, increases tumor-related variants through m6A-dependent manner, thereby promoting lymphatic metastasis in CCa. We found that HNRNPC overexpression correlates with lymphatic metastasis and poorer prognoses in CCa patients. Functionally, knocking down HNRNPC markedly inhibited the migration and invasion of several CCa cell lines, while supplementing HNRNPC restored the malignant phenotypes of these cells. Mechanistically, HNRNPC regulates exon skipping of FOXM1 by binding to its m6A-modified motif. Mutating the m6A site on FOXM1 weakened the interaction between HNRNPC and FOXM1 pre-RNA, leading to a reduction in the metastasis-related FOXM1-S variant. In conclusion, our findings demonstrate that m6A-dependent alternative splicing mediated by HNRNPC is essential for lymphatic metastasis in CCa, potentially providing novel clinical markers and therapeutic strategies for patients with advanced CCa.

A boy with a progressive neurologic decline harboring two coexisting mutations in KMT2D and VPS13D.

INTRODUCTION: Kabuki syndrome (KS) and spinocerebellar ataxia (SCA) are both rare conditions with neurodevelopmental abnormalities. Approaching a patient with complex phenotypes and differentiating the role of mutations may be beneficial but challenging in predicting the disease prognosis. CASE PRESENTATION: A boy presented with progressive ataxia, developmental regression, and myoclonus since 4 years of age. Additional features included growth hormone deficiency, excessive body hair, dysmorphic facies, hypoparathyroidism, and bilateral sensorineural hearing impairment. Brain magnetic resonance imaging depicted T2-weighted hyperintensities over bilateral globus pallidus, thalamus, subcortical white matter, and brainstem. The results of tandem mass spectrometry, mitochondrial deletion, and mitochondrial DNA sequencing were inconclusive. Whole-exome sequencing (WES) on genomic DNA obtained from peripheral blood cells revealed a known pathogenic variant at KMT2D gene (c.5993A > G, p.Tyr1998Cys) related to KS and two compound heterozygous, likely pathogenic variants at VPS13D gene (c.908G > A, p.Arg303Gln and c.8561T > G, p.Leu2854Arg) related to autosomal recessive SCA type 4 (SCAR4). DISCUSSION: SCAR4 is mainly adult-onset, but a few pediatric cases have recently been reported with progressive gait instability and developmental delay. The VPS13D gene has been suggested to play a role in mitochondrial size, autophagy, and clearance, thus explaining the clinical and imaging phenotypes. CONCLUSION: Our case showed a rare co-existence of KS and SCAR4, highlighting the utility of WES in atypical cases that a single-gene disease cannot fully explain.

Correlates of disordered eating and insulin restriction behavior and its association with psychological health in Taiwanese youths with diabetes mellitus.

BACKGROUND: Adolescents and young adults (AYAs) with diabetes mellitus (DM) are prone to eating disorders that may worsen metabolic control. This study investigated the clinical and behavioral correlates of disordered eating and insulin restriction (DE/IR) behavior and its association with psychological health among AYAs with DM. METHODS: We enrolled patients with DM aged 10-30 years receiving insulin treatment in a tertiary medical center from 2019 to 2021. After obtaining informed consent, we assessed various visit-to-visit HbA1c measures indicating glycemic control, DE/IR behavior using the modified SCOFF questionnaire, weight-control practices (e.g., self-medication, induced vomiting, and over-exercising), and anxious and depressive symptoms using the Hospital Anxiety and Depression Scale. Correlation and hierarchical regression analyses were applied to understand the clinical and behavioral correlates of DE/IR behavior and its association with anxiety and depression. RESULTS: Among the 110 patients with type 1 and type 2 DM recruited, we found 17.6% restricting insulin use and 6.3% self-medicating for weight control (higher in type 2 DM than type 1 DM). Hierarchical regression analyses showed HbA1c standard deviation (odds ratio = 2.18, [95% confidence interval 1.07-4.42]), body image (1.83, [1.05-3.20]), and dieting (4.74, [1.70-13.23]) associated with DE/IR behavior. Moreover, DE/IR behavior was further associated with anxiety (1.17 [1.08-1.27]) and depression (1.12 [1.03-1.22]). CONCLUSION: DE/IR behavior is not uncommon among AYAs with DM, particularly those with type 2 DM, and may be associated with anxiety and depressive symptoms. In addition, HbA1c variability is correlated with DE/IR behavior, and the clinical implications need further exploration.

Enzyme replacement therapy for children with acid sphingomyelinase deficiency in the real world: A single center experience in Taiwan.

Background: Acid sphingomyelinase deficiency (ASMD) is a lysosomal storage disease with multi-systemic involvement, with no disease-modifying treatment available. Olipudase alfa is an investigational enzyme product developed to replace the deficient acid sphingomyelinase in ASMD patients. Several clinical trials have reported promising safety and efficacy results in adult and pediatric patients. However, no data have been reported outside of the clinical trial setting yet. This study aimed to evaluate major outcomes in pediatric chronic ASMD patients receiving olipudase alfa in the real-world setting. Materials and methods: Two children with type A/B (chronic neuropathic) ASMD have received olipudase alfa treatment since May 2021. Clinical parameters, including height, weight, complete blood count, liver function tests, lipid profiles, biomarkers, abdominal ultrasonography with shear wave elastography, chest computed tomography, nerve conduction studies, neurodevelopmental evaluations, and six-minute walk tests, were checked at baseline and every three to six months in the first year of enzyme replacement therapy (ERT) to assess its efficacy and safety. Results: The two patients in our study started olipudase alfa treatment at the age of 5 years and 8 months and 2 years and 6 months. During the first year of treatment, both patients saw a reduction in their hepatic and splenic volumes as well as liver stiffness. Height z-score, weight z-score, lipid profiles, biomarker levels, interstitial lung disease scores, and bone mineral densities also improved over time. The six-minute walk test showed a gradual increase in walking distance in both patients. There were no obvious improvements or deterioration in neurocognitive function and peripheral nerve conduction velocities after treatment. No severe infusion-associated reactions were noted during the first year of treatment. One patient had two episodes of transient but significantly elevated liver enzymes during the dose-escalation phase. The patient was asymptomatic, and the impaired liver function resolved spontaneously within two weeks. Conclusion: Our results provide real-world experience that olipudase alfa is safe and effective in improving major systemic clinical outcomes for pediatric chronic ASMD patients. Monitoring of liver stiffness by shear wave elastography is a noninvasive procedure that can monitor treatment efficacy during ERT.

Postnatal Serum Total Thyroxine Level Associated with Short- and Long-Term Anthropometric Outcomes in Very Preterm Infants.

Thyroxine (T4) importantly regulates the growth of newborns. Compared to fetuses with equivalent gestational ages, very preterm infants (VPIs) often experience relatively low thyroxinemia, with a normal thyroid-stimulating hormone (TSH) concentration < 10 µIU/mL. However, there is continued debate regarding postnatal thyroxine supplementation for VPIs with normal TSH and transitionally low thyroxinemia. Little research has explored the role of the postnatal total T4 (TT4) serum concentration on the growth of VPIs. In this study, we aim to clarify whether the postnatal thyroxine concentration is associated with the short- and long-term growth outcomes of VPIs. A total of 334 surviving VPIs in our previously reported cohort, born in the period August 2007−July 2016, were enrolled. The exposure variable was the postnatal TT4 concentration at 1 month old. The primary outcomes were body weight increments over 28 days after the screening and anthropometric outcomes at the corrected age of 24 months old. Infants with any hormonal replacement, severe brain injury, congenital anomaly, or cerebral palsy were excluded. In total, 290 (86.8%) VPIs were included for analysis. In the 28 days after thyroid function screening, the TT4 concentration was found to have a significant association with positive increments in body weight (mean increment: 25.7 g per 1 µg/dL; p < 0.001) and a positive body weight z-score (mean increment: 0.039 per 1 µg/dL; p = 0.037), determined by generalized estimating equation analysis. At the corrected age of 24 months old, a higher postnatal TT4 concentration was associated with a lower body mass index (mean coefficient: −0.136; 95% CI: −0.231 to −0.041, p = 0.005) and lower body mass index z-score (mean coefficient: −0.097; 95% CI: −0.170 to −0.024, p = 0.009). Infants with a TT4 concentration > 6.4 ug/dL had significantly lower odds of overweight status (odds ratio: 0.365; 95% CI: 0.177 to 0.754, p = 0.006). We conclude that the postnatal TT4 concentration is associated with a positive increment in body weight in the short term. At the same time, the postnatal TT4 concentration is associated with lower odds of overweight status after long-term follow-up.

Postnatal Serum Total Thyroxine of Very Preterm Infants and Long-Term Neurodevelopmental Outcome.

Primary congenital hypothyroidism is a disease associated with low serum thyroxine and elevated thyroid-stimulating hormone (TSH) levels. The processes of screening and treating congenital hypothyroidism, in order to prevent neurodevelopmental impairment (NDI) in newborns, have been well investigated. Unlike term infants, very preterm infants (VPIs) may experience low thyroxine with normal TSH levels (<10.0 µIU/mL) during long-stay hospitalization. In the current literature, thyroxine treatment has been evaluated only for TSH-elevated VPIs. However, the long-term impact of low thyroxine levels in certain VPIs with normal TSH levels deserves more research. Since July 2007, VPIs of this study unit received screenings at 1 month postnatal age (PNA) for serum TSH levels and total thyroxine (TT4), in addition to two national TSH screenings scheduled at 3-5 days PNA and at term equivalent age. This study aimed to establish the correlation between postnatal 1-month-old TT4 concentration and long-term NDI at 24 months corrected age among VPIs with serial normal TSH levels. VPIs born in August 2007-July 2016 were enrolled. Perinatal demography, hospitalization morbidities, and thyroid function profiles were analyzed, and we excluded those with congenital anomalies, brain injuries, elevated TSH levels, or a history of thyroxine treatments. In total, 334 VPIs were analyzed and 302 (90.4%) VPIs were followed-up. The postnatal TT4 concentration was not associated with NDI after multivariate adjustment (odd ratios 1.131, 95% confidence interval 0.969-1.32). To attribute the NDI of TSH-normal VPIs to a single postnatal TT4 concentration measurement may require more research.

Epigenotype, Genotype, and Phenotype Analysis of Taiwanese Patients with Silver-Russell Syndrome.

BACKGROUND: Silver-Russell syndrome (SRS) is a clinically and genetically heterogeneous disorder characterized by severe intrauterine growth retardation, poor postnatal growth, characteristic facial features, and body asymmetry. Hypomethylation of the imprinted genes of the chromosome 11p15.5 imprinting gene cluster and maternal uniparental disomy of chromosome 7 (mUPD7) are the major epigenetic disturbances. The aim of this study was to characterize the epigenotype, genotype, and phenotype of these patients in Taiwan. METHODS: Two hundred and six subjects with clinically suspected SRS were referred for diagnostic testing, which was performed by profiling the methylation of H19-associated imprinting center (IC) 1 and the imprinted PEG1/MEST region using methylation-specific multiplex ligation-dependent probe amplification and high-resolution melting analysis with a methylation-specific polymerase chain reaction assay. We also applied a whole genome strategy to detect copy number changes and loss of heterozygosity. Clinical manifestations were recorded and analyzed according to the SRS scoring system proposed by Bartholdi et al. Results: Among the 206 referred subjects, 100 were classified as having a clinical diagnosis of SRS (score ≥ 8, maximum = 15) and 106 had an SRS score ≤ 7. Molecular lesions were detected in 45% (45/100) of the subjects with a clinical diagnosis of SRS, compared to 5% (5/106) of those with an SRS score ≤ 7. Thirty-seven subjects had IC1 hypomethylation, ten subjects had mUPD7, and three subjects had microdeletions. Several clinical features were found to be statistically different (p < 0.05) between the "IC1 hypomethylation" and "mUPD7" groups, including relative macrocephaly at birth (89% vs. 50%), triangular shaped face (89% vs. 50%), clinodactyly of the fifth finger (68% vs. 20%), and SRS score (11.4 ± 2.2 vs. 8.3 ± 2.5). CONCLUSIONS: The SRS score was positively correlated with the molecular diagnosis rate (p < 0.001). The SRS subjects with mUPD7 seemed to have fewer typical features and lower SRS scores than those with IC1 hypomethylation. Careful clinical observation and timely molecular confirmation are important to allow for an early diagnosis and multidisciplinary management of these patients.

The relationship between nonalcoholic fatty liver disease and pediatric congenital hypothyroidism patients.

Previous studies have shown hypothyroidism was independently associated with nonalcoholic fatty liver disease (NAFLD) in adults, but few studies examined their relationships in pediatric populations. This study aimed to investigate the prevalence of NAFLD in pediatric congenital hypothyroidism (CHT) patients and to identify the association between CHT and NAFLD. This study enrolled pediatric CHT patients receiving levothyroxine treatment at one medical center from 2013 to 2014. Euthyroid subjects (ET) and transient hypothyroidism (THT) patients weaned off medication successfully after age 3 were selected for further comparison. Laboratory data including thyroid functions, liver functions, and metabolic profiles were obtained. The major outcome was the occurrence of NAFLD, diagnosed based on the findings of abdominal ultrasonography. One-hundred and twenty-nine subjects (47 in CHT, 47 in THT, and 35 in ET groups) were enrolled. The analysis showed higher fasting serum glucose, insulin, thyroxine (T4), and mean thyroid-stimulating hormone (TSH) levels in the CHT group. NAFLD prevalence was higher in the CHT (23.4%) group than in the THT (8.5%) and the ET (5.7%) groups, demonstrating an increasing trend across three strata (X2 linear-by-linear = 5.9, P < .05). The multivariate regression analysis showed obesity (ß-coefficient = 5.52, P < .05), CHT (ß-coefficient = 2.92, P < .05) and mean TSH levels (ß-coefficient = 0.24, P < .05) were independent risk factors for NAFLD. A positive correlation was found between TSH level and lipid profiles. CHT patients had higher risk of NAFLD despite treatment being initiated early in life. Close monitoring of metabolic profiles is warranted. Further research should examine ways to optimize the treatment for CHT patients in terms of prevention against NAFLD.