Genetic screening of a Chinese cohort of children with hearing loss using a next-generation sequencing panel.

BACKGROUND: At present, the hereditary hearing loss homepage, ( https://hereditaryhearingloss.org/ ), includes 258 deafness genes and more than 500 genes that have been reported to cause deafness. With few exceptions, the region-specific distributions are unclear for many of the identified variants and genes. METHODS: Here, we used a custom capture panel to perform targeted sequencing of 518 genes in a cohort of 879 deaf Chinese probands who lived in Yunnan. Mutation sites of the parents were performed by high-throughput sequencing and validated by Sanger sequencing. RESULTS: The ratio of male to female patients was close to 1:1 (441:438) and the age of onset was mainly under six. Most patients (93.5%) were diagnosed with moderate to severe deafness. Four hundred and twenty-eight patients had variants in a deafness gene, with a detection rate of 48.7%. Pathogenic variants were detected in 98 genes and a number of these were recurrent within the cohort. However, many of the variants were rarely observed in the cohort. In accordance with the American College of Medical Genetics and Genomics, pathogenic, likely pathogenic and variants of uncertain significance accounted for 34.3%, 19.3% and 46.4% of all detected variants, respectively. The most common genes included GJB2, SLC26A4, MYO15A, MYO7A, TMC1, CDH23, USH2A and WFS1, which contained variants in more than ten cases. The two genes with the highest mutation frequency were GJB2 and SLC26A4, which accounted for 28.5% (122/428) of positive patients. We showed that more than 60.3% of coding variants were rare and novel. Of the variants that we detected, 80.0% were in coding regions, 17.9% were in introns and 2.1% were copy number variants. CONCLUSION: The common mutation genes and loci detected in this study were different from those detected in other regions or ethnic groups, which suggested that genetic screening or testing programs for deafness should be formulated in accordance with the genetic characteristics of the region.

An unusually high prevalence of allergic rhinitis at high altitudes in 6-7 year old children - An epidemiological study.

Objectives: To compare the epidemiology and disease patterns of allergic rhinitis (AR) at 2 different altitudes in children aged 6-7 years, and subsequently to compare with and augment data from international studies. Materials and methods: This is a multistage, clustered and stratified random sample study. The study area comprises 2 distinct areas within Yunnan Province, China. Low altitude was represented by Xishuangbanna Prefecture (XB), while high altitude was represented by Diqing Prefecture (DiQ). Each study area was subdivided into 3 sub-areas, and children aged 6-7 years were randomly sampled based on proportion-weighted sampling. The area studied includes the well-known area of Shangri-La city. Questionnaires were distributed and jointly completed by study participants and their parents or guardians, under the guidance of professional medical staff. Results: 2796 valid questionnaires out of 2933 distributed were obtained (survey response rate 95.3%). The prevalence of AR is statistically significantly higher at high altitude (DiQ, 36.0%, 95%CI 33.2-38.8) as compared to low altitude (XB, 19.7%, 95%CI 17.8-21.6) (p < 0.001). Both areas studied had a greater prevalence of AR compared to international data. In both XB and DiQ, male gender, history of early antibiotic use, urban place of birth and place of residence, presence of smokers within the same household, family history of allergic diseases (such as atopic dermatitis), as well as higher parental educational level were all associated with a higher prevalence of AR (p < 0.05). In DiQ, the prevalence of AR in Han ethnicity was greater than that of ethnic minorities (p < 0.05). In XB, being a single child was associated with an increased prevalence of AR compared to those who had siblings (p < 0.05). Conclusion: Our study found that the prevalence of AR is relatively greater at higher altitudes. Genetic and environmental factors both play an important role in the pathogenesis of AR. While altitude may be an important environmental factor, confounding factors may include humidity, temperature and distribution pattern of common aeroallergens.

The Role of CT Scan in Pediatric Airway Foreign Bodies.

Objective: We aim to determine the utility of CT scan as a method to accurately confirm pediatric airway foreign bodies (AFBs), the current gold standard of which is chest X-ray as the primary imaging modality in the investigation screening of AFBs with progression to microlaryngobronchoscopy. Methods: A retrospective cohort study of children diagnosed with suspected AFBs between July 2019 and June 2020 was conducted. The primary outcome of missed AFBs from radiologic investigations was recorded. Results: A total of 226 children with an average age of 1.94 years were included in this study. One hundred and two children were eventually admitted to the hospital for microlaryngobronchoscopy. A total of 89 cases were initially examined by chest X-ray with the diagnosis confirmed in 26 cases. The initial examination was chest CT scan in 105 cases, of which the diagnosis was confirmed in 46 cases. The initial examination was chest CT scan with airway reconstruction in 32 cases, and the diagnosis was confirmed in 17 cases. Patients with negative chest CT scan with airway reconstruction were observed to have resolution of symptoms with no further need for bronchoscopy. Conclusion: Chest CT scan with airway reconstruction had the highest rate of confirmed diagnosis of pediatric AFBs on initial scanning, followed by chest CT scan, and finally chest X-ray with fluoroscopy; there was no missed diagnosis in chest CT scan with airway reconstruction. Chest CT scan with airway reconstruction can accurately and quickly detect AFBs and reduce unnecessary bronchoscopy.

The emerging role of NR2F1-AS1 in the tumorigenesis and progression of human cancer.

Long noncoding RNAs (lncRNAs) are transcripts of more than 200 nucleotides that lack the ability to encode protein. Convincing studies have indicated that lncRNAs can act as oncogenes or tumor suppressors by regulating gene expression. The novel lncRNA NR2F1-AS1 was recently found to be abnormally expressed in various malignancies, including hepatocellular carcinoma, gastric cancer, colorectal cancer, pancreatic cancer, breast cancer, lung cancer, thyroid cancer, esophageal squamous cell carcinoma, osteosarcoma, and neuroblastoma. NR2F1-AS1 can modify cell proliferation, invasion, migration, apoptosis, the cell cycle, and glycolysis through various mechanisms involving direct or indirect effects on pathways. Furthermore, NR2F1-AS1 may be a potential therapeutic target and prognostic marker in cancer, as it has been related to the clinicopathological characteristics of cancer patients. Here, we summarize and clarify recent research advances regarding the expression, function, molecular mechanisms, and clinical implications of NR2F1-AS1 in multiple malignant tumors.

[Genotype and phenotype analysis of a family with Waardenburg syndrome type â caused by a novel mutation in PAX3 gene].

Objective:To identify gene mutation and analysis the association between clinical characterizes and the mutations in a family of Waardenburg syndrome （WS） type I in Yunnan, China. Methods:With informed consent, the proband with WS phenotype and his family members were given medical history collection, physical examination and audiological evaluation. Peripheral blood was obtained, genomic DNA was extracted, and deafness related genes were detected by high-throughput sequencing. Sanger sequencing was used to verify the mutation sites of proband and his family members. Results:C. 602C>G mutation in exon 5 of PAX3 gene was identified, which is nonsense mutation and may cause a truncated protein. The mutation cause 201 amino acid of the protein changed from serine to stop codon. According to the American College of Medical Genetics and Genomics （ACMG）, it is considered as Pathogenicity（PVS1+PM2+PP3）. This mutation has not been included in the database also not been reported in the literature. Conclusion:Combined with the results of clinical diagnosis and gene diagnosis, this mutation was considered as the cause of the disease. This study enriched mutation spectrum of PAX3 gene.

A novel mutation of the PAX3 gene in a Chinese family with Waardenburg syndrome type I.

BACKGROUND: To analyze the clinical phenotypes and genetic variants of a Chinese family with Waardenburg syndrome (WS) and to explore the possible molecular pathogenesis of WS. METHODS: The clinical data from a patient and his family were collected. The genomic DNA of the patient and his family was purified from their peripheral blood. All exons and flanking sequences of the MITF, PAX3, SOX10, SNAI2, END3, and EDNRB genes were investigated through high-throughput sequencing. Based on the results of high-throughput sequencing, genetic variants in the patient and his family were verified and analyzed by Sanger sequencing. RESULTS: The patient was diagnosed with typical WS1 that manifested in hearing impairment, inner canthus ectopia and heterochromic iris. Sanger sequencing revealed the pathogenic heterozygous c.420-424de1CGCGGinsTTAC mutation in the PAX3 gene in the proband, which is a frameshift mutation that changed the amino acid sequence of the PAX3 protein from AVCDRNTVPSV to YSVIETPCRQ* (* refers to a stop codon) from amino acids 141-151. The stop codon induced by this mutation resulted in the truncation of the PAX3 protein. The same mutation sites were also found in the mother and younger sister of the proband. No previous report of this mutation was found in the Human Gene Mutation Database. CONCLUSION: The novel heterozygous c.420-424de1CGCGGinsTTAC mutation is the molecular pathological cause for WS1 in our patient. The clinical and genetic characterization of this family with WS1 elucidated the genetic heterogeneity of PAX3 in WS1. Moreover, the mutation detected in this case has expanded the database of PAX3 mutations.