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Aims: Van der Woude syndrome (VWS) is one of the most common craniofacial anomalies, causing significant functional and psychological burden to the patients. This study aimed to identify the genetic cause of VWS in a Chinese family. Methods: Whole genome sequencing (WGS) was performed to screen for pathogenic mutations. Various Bioinformatics tools were used to assess the pathogenicity of the variants. Cosegregation analysis of the candidate variant was carried out. Interpretation of variants was performed according to the American College of Medical Genetics and Genomics guidelines. Results: A novel frameshift duplication c.373_374dupAA (p.Asn125Lys fs*43) was identified in exon 4 of the interferon regulatory factor 6 (IRF6) gene in all 3 affected members, which were not found in unaffected family members. The novel mutation leads to a frameshift and a premature stop codon which caused putative truncated protein. Protein alignment indicated high evolutionary conservation of the p.N125 residue, and this mutation was predicted by online tools to be damaging and deleterious. Conclusions: This study demonstrates that the novel mutation c.373_374dupAA (p.Asn125Lysfs*43) in the IRF6 gene corresponds to the VWS in this family. The discovery of this pathogenic variant enriches the genotypic spectrum of IRF6 gene and contributes to genetic diagnosis and counseling of families with VWS. [ABSTRACT FROM AUTHOR]

Background: Bacterial pathogens are a major cause of childhood community acquired lower respiratory tract infections (CA-LRTIs), and few data described the impact of antimicrobial resistance on children with CA-LRTIs. This study aims to investigate the antimicrobial resistance in common bacterial agents among hospitalized children with CA-LRTIs between 2011 and 2016 in Dongguan, China.Methods: Sputum samples were collected from hospitalized children (0-5 years old) with CA-LRTIs in Dongguan Children's Hospital. Bacterial pathogens were detected using traditional culture methods, and disc diffusion tests were used to determine antibiotic resistance.Results: Among the 2360 samples analyzed, 342 (14.5%) were positive for bacterial infection. The most prevalent pathogen was MSSA (2.3%), followed by MRSA (1.5%), E. coli (1.7%), E. coli ESBLs (1.2%), K. pneumonia ESBLs (1.5%), K. pneumonia (1.4%) and S. pneumonia (1.3%). Of the hospitalized patients with bacteria causing of CA-LRTIs, 90.1% were less than 1-year-old. MSSA and MRSA were more commonly isolated in infants less than 3 months. E. coli, K. pneumonia and K. pneumonia ESBLs were more common bacteria causing CA-LRTIs in infants less than 1 month. Resistance levels to penicillins, fluoroquinolones, macrolides, cephalosporins, carbapenems and vancomycin varied in different bacteria.Conclusions: S. aureus, E coli and K. pneumonia were the common bacterial isolates recovered from chidren with CA-LTRIs during 2011-2015. Age group of under 1 year old was at a high risk of bacterial infections. Many isolates showed antibiotic resistance level was associated with antibiotic usage in clinic. Increasing surveillance of antibiotic resistance is urgently needed and develops better strategies to cure the antibiotic abuse in China. [ABSTRACT FROM AUTHOR]

Aims: Van der Woude syndrome (VWS) is one of the most common craniofacial anomalies, causing significant functional and psychological burden to the patients. This study aimed to identify the genetic cause of VWS in a Chinese family., Methods: Whole genome sequencing (WGS) was performed to screen for pathogenic mutations. Various Bioinformatics tools were used to assess the pathogenicity of the variants. Cosegregation analysis of the candidate variant was carried out. Interpretation of variants was performed according to the American College of Medical Genetics and Genomics guidelines., Results: A novel frameshift duplication c.373_374dupAA (p.Asn125Lys fs*43) was identified in exon 4 of the interferon regulatory factor 6 (IRF6) gene in all 3 affected members, which were not found in unaffected family members. The novel mutation leads to a frameshift and a premature stop codon which caused putative truncated protein. Protein alignment indicated high evolutionary conservation of the p.N125 residue, and this mutation was predicted by online tools to be damaging and deleterious., Conclusions: This study demonstrates that the novel mutation c.373_374dupAA (p.Asn125Lysfs*43) in the IRF6 gene corresponds to the VWS in this family. The discovery of this pathogenic variant enriches the genotypic spectrum of IRF6 gene and contributes to genetic diagnosis and counseling of families with VWS.

Background: Thalassemia is a common inherited hematological disease in tropical and subtropical regions. This study aimed to investigate the mutation spectrum of thalassemia in the Dongguan region of southern China and comprehensively analyze hematologic features of thalassemia carriers with various types of globin mutations., Methods: A hematological screening including hematological indices such as mean corpuscular volume (MCV), mean corpuscular hemoglobin content (MCH), and mean corpuscular hemoglobin concentration (MCHC) was conducted in 19 442 people from Dongguan region, Guangdong province of China. Then, 4891 suspected thalassemia carriers were further investigated by genetic analysis of combined NGS and gap-PCR., Results: Totally, 2319 (11.9%) cases were diagnosed as carriers of thalassemia, of which 1483 cases (7.6%) were α-thalassemia, 741 cases (3.8%) were β-thalassemia, and 95 cases (0.5%) were co-inheritance of α- and β-thalassemia. In α-thalassemia carriers, the phenotypic severity increases with the number of nonfunctional α-globin genes. The patients with - SEA /α WS α genotype have less severe clinical phenotypes than those with other Hb H diseases. As for β-thalassemia, the MCV and MCH in both β 0 and β + carriers are markedly reduced., Conclusions: This is the first comprehensive molecular epidemiological survey and hematological profiling of thalassemia in Dongguan area. This study will be benefit for genetic counseling in the clinic and may help pediatricians to make a correct diagnosis of different types of thalassemia., (© 2020 The Authors. Journal of Clinical Laboratory Analysis Published by Wiley Periodicals LLC.)

Objective: The purpose of this study is that analyze the clinical characters of Treacher Collins syndrome (TCS) with the de nove TCOF1 mutation and emphasize the genetic research result., Methods: Genomic DNA from the proband and his parents were extracted from 200 to 400 μl of peripheral blood samples. A 4000 pathgenic genes diagnostic screening panel developed by our laboratory group was used for gene mutation screening. The panel covered the TCOF1 (NM_001135243.1), POLR1C (NM_203,290) and POLR1D (NM_015,972) genes associating with TCS., Results: We reported a case of typical, complete syndrome with a nonsense mutation c.1622G > A (p.W541*) in exon 11 of TCOF1, who presents bilateral external ears abnormalities, atresia of external auditory canals, antimongoloid slant of the eyes, bilateral partial coloboma of the lateral part of the lower lids, a large and protruding nose, macrostomia, cleft palate and hair displacement anterior to the auricle., Conclusions: Our report expands the spectrum of known pathogenic TCOF1 variants associated with TCS in humans.TCOF1 deficiency may cause a severe neonatal presentation with birth defects., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Polydactyly is one of the most common congenital limb abnormalities. Our objective was to identify the genetic causes of non-syndromic polydactyly in 78 Chinese children., Materials and Methods: Genomic DNA was isolated from 78 independent nonsyndromic polydactyly patients, of whom 71 had preaxial polydactyly (PPD), six had postaxial polydactyly (PAP), and one showed combined PPD1 and PAP-A/B. The coding areas and exon/intron boundaries of the GLI3 and SHH genes and the genomic region of SHH ZRS were amplified by polymerase chain reaction and sequenced., Results: The patient with combined PPD1 and PAP-A/B (subject DUO36) exhibited a heterozygous nonsense mutation in chr7: 42004164G>A (ENST00000395925, c.4507C>T, p.Gln1503Stop ) of the GLI3 gene that has not been previously recorded. We did not detect any mutations in GLI3, SHH, or SHH ZRS in the other 77 nonsyndromic polydactyly patients., Conclusion: The novel mutation in GLI3 c.4507C>T is likely one of the causes of the PAP and PPD1 of subject DUO36. This important finding should facilitate the optimization of genetic testing for nonsyndromic polydactyly.

The mechanism of the coexistence of HBsAg and anti-HBs is still unclear. This study investigated the variations located in the major hydrophilic region (MHR) of HBV from individuals with simultaneous HBsAg and anti-HBs in Guangzhou, southern China. Among 4455 samples analyzed, 179 (4.02%) patients were discovered with both HBsAg and anti-HBs. Finally, 44 individuals with concurrent HBsAg and anti-HBs (defined as group I), and 88 patients with positive HBsAg and negative anti-HBs (defined as group II, served as control) were enrolled in the study. The number of residue changes per 100 residues within the MHR in group I was 7.1 times more frequent than group II (P < 0.001) and was discovered mostly in the MHR1 (aa99-119) (P < 0.001). Two or more residue changes in the MHR were discovered in 15 patients (34.1%) of group I, but were found in only one (1.1%) patient of group II (P < 0.001). The most common variants in group I were at positions s101Q, s133M, s126T/I, s131T, s145G, s120P, and s129Q. In addition, sQ101 K, sT131N, and sM133L were more frequently discovered in group I with significant difference (P < 0.05). In chronic hepatitis B (CHB) patients, the simultaneous of HBsAg and anti-HBs were accompanied with an increase of MHR variants, and suggested that the HBsAg mutants were selected by naturally acquired anti-HBs during chronic carriage., (© 2018 Wiley Periodicals, Inc.)

Background: Bacterial pathogens are a major cause of childhood community acquired lower respiratory tract infections (CA-LRTIs), and few data described the impact of antimicrobial resistance on children with CA-LRTIs. This study aims to investigate the antimicrobial resistance in common bacterial agents among hospitalized children with CA-LRTIs between 2011 and 2016 in Dongguan, China., Methods: Sputum samples were collected from hospitalized children (0-5 years old) with CA-LRTIs in Dongguan Children's Hospital. Bacterial pathogens were detected using traditional culture methods, and disc diffusion tests were used to determine antibiotic resistance., Results: Among the 2360 samples analyzed, 342 (14.5%) were positive for bacterial infection. The most prevalent pathogen was MSSA (2.3%), followed by MRSA (1.5%), E. coli (1.7%), E. coli ESBLs (1.2%), K. pneumonia ESBLs (1.5%), K. pneumonia (1.4%) and S. pneumonia (1.3%). Of the hospitalized patients with bacteria causing of CA-LRTIs, 90.1% were less than 1-year-old. MSSA and MRSA were more commonly isolated in infants less than 3 months. E. coli, K. pneumonia and K. pneumonia ESBLs were more common bacteria causing CA-LRTIs in infants less than 1 month. Resistance levels to penicillins, fluoroquinolones, macrolides, cephalosporins, carbapenems and vancomycin varied in different bacteria., Conclusions: S. aureus, E coli and K. pneumonia were the common bacterial isolates recovered from chidren with CA-LTRIs during 2011-2015. Age group of under 1 year old was at a high risk of bacterial infections. Many isolates showed antibiotic resistance level was associated with antibiotic usage in clinic. Increasing surveillance of antibiotic resistance is urgently needed and develops better strategies to cure the antibiotic abuse in China.

Background: Congenital deafness is one of the most distressing disorders affecting humanity and exhibits a high incidence worldwide. Most cases of congenital deafness in the Chinese population are caused by defects in a limited number of genes. A convenient and reliable method for detecting common deafness-related gene mutations in the Chinese population is required., Methods: We developed a PCR-reverse dot blot (RDB) assay for screening 20 hotspot mutations of GJB2, GJB3, SLC26A4, and MT-RNR1, which are common non-syndromic hearing loss (NSHL)-associated genes in the Chinese population. The PCR-RDB assay consists of multiplex PCR amplifications of 10 fragments in the target sequence of the four above-mentioned genes in wild-type and mutant genomic DNA samples followed by hybridization to a test strip containing allele-specific oligonucleotide probes. We applied our method to a set of 225 neonates with deafness gene mutations and 30 normal neonates., Results: The test was validated through direct sequencing in a blinded study with 100% concordance., Conclusions: The results demonstrated that our reverse dot blot assay is a reliable and effective genetic screening method for identifying carriers and individuals with NSHL among the Chinese population.

Objective: The goal of this study was to investigate the use of concurrent genetic screening together with standard newborn hearing screening (NHS) in an effort to provide a scientific basis for the beneficial use of concurrent genetic hearing screening in newborns. Our aim was to improve the neonatal detection rate of hearing impairment and the potential for hearing loss, allowing for increased early intervention and potentially allowing for prevention of later onset hearing loss. This information could also be used to increase the effectiveness of genetic counseling regarding hearing impairment., Methods: A total of 9317 neonates from Children's Hospital of Dongguan and Dongguan People's Hospital were included in this study between January 2015 and October 2015. Twenty hotspot hearing-associated mutations of four common deafness- susceptibility genes (GJB2, GJB3, SLC26A4, and MTRNR1) were analyzed by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The results of genetic screening and NHS were concurrently analyzed., Results: A total of 129 infants (1.38%) exhibited hearing loss as determined by otoacoustic emission (OAE) testing. The genetic screening revealed that 348 (3.74%) individuals had at least one mutant allele. In total, 34 (0.36%) of the neonates carried a causal complement of mutations. The overwhelming majority of the genetically referred newborns passed the OAE hearing screening, but could be at risk for later hearing loss., Conclusion: This study furthers the understanding of the etiology of hearing loss and proves that it is beneficial to use genetic screening along with OAE screening of neonates to improve detection rates of at-risk infants. Our results show that this concurrent testing allows for better early identification of infants at risk for hearing loss, which may occur before speech and language development. Prevention of hearing loss can be achieved by avoiding the use of antibiotics containing amino glycosides in infants whose mutations make them extremely sensitive to these antibiotics. This information is also useful in genetic counseling, providing region-specific mutation information.

The PIK3CA mutation has been extensively reported in the setting of cancers; however, the clinicopathological significance of PIK3CA expression has rarely been discussed in esophageal squamous cell carcinoma. In the present study, to confirm the significance of PIK3CA expression in association with metastasis and prognosis, which has been somewhat controversial in esophageal squamous cell carcinoma (ESCC), the relationship between clinicopathological features of ESCC and PIK3CA expression was analyzed using immunohistochemistry with a tissue microarray. Meanwhile, as additional verification and an ethnic control, another independent small cohort of Kazakh ESCC were analyzed by immunohistochemistry. To investigate the pilot role of PIK3CA in ESCC cells, ESCC cell lines ECa109 and EC9706 were transiently transfected with specific siRNA against PIK3CA. The silencing effect was detected by Western blot. Cell proliferation was examined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay; apoptosis and the cell cycles were analyzed by flow cytometry. Furthermore, the migratory and invasive ability were evaluated by wound healing and transwell invasion assay, respectively. Expression of PIK3CA was significantly higher in ESCC than in paired normal controls and was ethnicity independent; no statistically significant difference was observed between PIK3CA expression and sex, age, depth of invasion, tumor differentiation, lymph node metastasis, or prognosis. Proliferation, migration, and invasion were all markedly reduced after knockout of PIK3CA. Moreover, the cell cycle was arrested at the S phase, and the apoptosis rate was significantly increased, suggesting that PIK3CA plays a key role in promoting the proliferation and motility of ESCC cells., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Antigen-presentation genes play a vital role in the pathogenesis of HCV infection. However, the relationship of variants of these genes with spontaneous outcomes of HCV infection has not been fully investigated. To explore novel loci in the Chinese population, 34 tagging-SNPs in 9 candidate genes were genotyped for their associations with the outcomes of HCV infection. The distributions of different genotypes and haplotypes were compared among 773 HCV-negative controls, 246 subjects with HCV natural clearance, and 218 HCV persistent carriers recruited from hemodialysis patients and intravenous drug users. Our study implicated that TAP2, HLA-DOA, HLA-DOB, and tapasin loci were novel candidate regions for susceptibility to HCV infection and viral clearance in the Chinese population. Logistic regression analyses showed that TAP2 rs1800454 A (OR = 1.48, P = 0.002) and HLA-DOB rs2071469 G (OR = 1.23, P = 0.048) were significantly associated with increased susceptibility to establishment of HCV infection. However, high-risk behavior exposure and age were stronger predictors of HCV infection. Mutation of tapasin rs9277972 T (OR = 1.57, P =0.043) increased the risk of HCV chronicity, and HLA-DOA rs3128935 C (OR = 0.62, P = 0.019) increased the chance of viral resolution. With regards to the effect of rs3128925, interactions were found with high-risk behavior (P = 0.013) and age (P = 0.035). The risk effect of rs3128925 T for persistent HCV infection was higher in injecting drug users (vs. dialysis patients) and in subjects ≥ 40 years old (vs. < 40 years old).

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common enzymatic disorder of the erythrocytes that affects 400 million people worldwide. We developed a PCR-reverse dot blot (RDB) assay to screen twenty genotypes of seventeen Chinese G6PD mutations and investigate the spectrum of G6PD deficiency mutations in Dongguan District, Guangdong Province, in southern China., Method: The PCR-RDB assay consists of multiplex PCR amplification of seven fragments in the G6PD target sequence of wild-type and mutant genomic DNA samples followed by hybridization to a test strip containing allele-specific oligonucleotide probes. A total of 16,464 individuals were analyzed by a combination of phenotypic screening and genotypic detection using the PCR-RDB assay and DNA sequence analysis., Results: The PCR-RDB assay had a detection rate of 98.1%, which was validated by direct sequencing in a blind study with 100% concordance. The G6PD deficiency incidence rate in Dongguan District is 4.08%. Thirty-two genotypes from 469 individuals were found. The two most common variants were c.1376G>T and c.1388G>A, followed by c.95A>G, c.871G>A, c.392G>T, and c.1024 C>T. In addition, two rare mutations (c.703C>A and c.406C>T) were detected by DNA sequencing analysis. In our study, 65 cases harbored the C1311T/IVS polymorphism and 67 cases were homozygote., Conclusion: The PCR-RDB assay we established is a reliable and effective method for screening G6PD mutations in the Chinese population. Data on the spectrum of mutations in the Dongguan District is beneficial to the clinical diagnosis and prevention of G6PD deficiency.

Background: Genes related to antigen presentation pathway, which are in the non-classical class-II region of human leukocyte antigen (HLA), play a vital role during the infection of hepatitis C virus (HCV)., Methods: The current study determined the genotypes of 34 tagging-SNPs (single nucleotide polymorphisms) from 9 candidate genes (HLA-DMA, HLA-DMB, HLA-DOA, HLA-DOB, TAP1, TAP2, LMP2, LMP7, and tapasin) in a Chinese population of paid blood donors with high risk of HCV infection. The distributions of those SNPs were compared among the 1207 former paid blood donors with different HCV infection outcomes., Results: HLA-DMA rs1063478 and HLA-DOA rs2284191 were independent factors of acquiring HCV infection. Carrying three favorable alleles of rs1063478-T and rs2284191-G offered the highest protective effect (odds ratio = 0.46, 95% confidence intervals = 0.27-0.78). HLA-DOB rs7383287 and LMP2 rs17587 were independent factors of infection chronicity. Subjects carrying two favorable alleles of rs7383287-G and rs17587-A had a decreased risk of HCV chronicity (odds ratio = 0.42, 95% confidence intervals = 0.26-0.66). The interaction analysis showed that experience of plasma donation interacted with the combined effects of rs1063478 and rs2284191 for HCV susceptibility, and the experience of whole blood donation interacted with the association of rs7383287 with HCV clearance., Conclusions: Our results suggested that genetic variants in antigen presentation pathway had influence on susceptibility to HCV infection and viral clearance. HLA-DMA rs1063478, HLA-DOA rs2284191, and HLA-DOB rs7383287 were identified as novel loci in Chinese population that were involved in HCV infection.