Objective To comprehensively investigate the levels of exposure and distribution characteristics of trihalomethanes (THMs) in drinking water in Guangzhou City, and evaluate the health risks of different groups of children, adolescents and adults, and to provide data and evidence for protecting human health and promoting risk control of drinking water. Methods According to the technical requirements of the ^"Standards for Drinking Water Quality Testing Methods^" (GB/T 5750-2023), the concentration of THMs, including trichloromethane (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and tribromomethane (TBM) in drinking water in Guangzhou City from 2023-2024 were detected. The health risk model recommended by USEPA was used for risk assessment．Results TCM, BDCM and DBCM were detected in the factory water and terminal water, with TCM contributing the most. There was a statistically significant difference (P<0.05) between the wet and dry seasons, and the concentration of TCM in the wet season was higher than that in the dry season. Among the multiple exposure factors, the amount of exposure through drinking water intake was much greater than that through skin absorption. The carcinogenic risk index of THMs for children, adolescents, and adults was 22.0×10^-6, 12.2×10^-6, and 11.4×10^-6, respectively, while the non-carcinogenic risk was less than 1. Conclusion The exposure risks of THMs in children, adolescents, and adults is within an acceptable range, but monitoring needs to be strengthened, with a particular focus on children.

Objective:To explore the clinical phenotypes and genetic characteristics of a pedigree with Distal arthrogryposis type 5D (DA5D) caused by compound heterozygous variants in the ECEL1 gene. Methods:A child (proband) diagnosed with DA5D and his family members (proband′s parents and sister) who was admitted to the Department of Rehabilitation Medicine of Henan Children′s Hospital in July 2022 due to " multiplex distal arthrogryposis" were enrolled into this study. Clinical data of the proband were collected and peripheral blood samples were obtained from the proband and members of his family about 3 mL. Trio-whole genome sequencing (trio-WGS) was carried out to detected the genetic variations of the proband and his family members. The candidate′s pathogenic gene variants were screened and analyzed by Genome Aggregation Database (gnomAD) and other databases. The screened variants wer annotated for clinical phenotypes using databases like the Online Mendelian Inheritance in Man (OMIM). The pathogenicity of the candidate variants was predicted by bioinformatics tools such as Provean. Based on the guidelines of the American College of Medical Genetics and Genomics (ACMG), pathogenicity ratings were conducted for variant sites. The protein conservation and mutation structure prediction of ECEL1 protein among species were carried out though MEGA-X and PyMOL. The research protocol of this study was reviewed by the Ethics Committee of Henan Provincial Children′s Hospital (Approval No. 2023-H-H01), and informed consent for clinical research was obtained from the guardians of the probands.Results:The proband had multiplex distal arthrogryposis involving hands, feet, knees, and ankles, and had right ptosis, micrognathia, low auricular position, and upturned nose. The parents and sister both had normal phenotypes. Trio-WGS and Sanger sequencing revealed that the child had compound heterozygous variants of paternal c. 1742_c.1743insT and maternal c. 2314T>G, for which the father and sister were carriers of the c. 1742_c.1743insT heterozygous variant and the mother was carrier of c. 2314T>A. Neither mutation site has been reported. According to guidelines of ACMG, the c. 1742_c.1743insT variant was classified as likely pathogenic (PSV1+ PM2_Supporting), and c. 2314T>G was classified as uncertain (PM2_Supporting+ PM3+ PP3). The results of conserved analysis of amino acid residue sequences of ECEL1 protein showed that the missense mutation of the maternal c. 2314T>G(p.Cys772Gly) was highly conserved among humans and other seven species. The protein structure prediction revealed that the c.1742_c.1743insT frameshift mutation led to the protein truncation, and the c. 2314T>G missense mutation resulted in the failure of forming 1 disulfide bond.Conclusion:The compound heterozygous variants of ECEL1 gene were considered to be pathogenic for this DA5D patient, which have expanded the mutational spectrum of the ECEL1 gene and provided a reference for clinical diagnosis as well as genetic counseling for this family.

Objective:To explore the clinical phenotype and genetic characteristics of a child with neurodevelopmental disorder caused by homozygous frameshift variant of the TRAPPC6B gene, and to provide reference for the diagnosis of the disease. Methods:A child with neurodevelopmental disorder caused by homozygous variant of TRAPPC6B gene who was admitted to the Children′s Hospital Affiliated to Zhengzhou University in March 2023 due to " inability to stand and walk independently at 1 year and 3 months old" was selected as the study object. The clinical data were collected by retrospective analysis method. Target region high-throughput sequencing was carried out on the child and parental peripheral blood samples, and candidate variant was verified by Sanger sequencing and bioinformatic analysis. The pathogenicity of variant was rated according to the Standards and Guidelines for the Interpretation of Sequence Variants released by American College of Medical Genetics and Genomics (ACMG) (hereinafter referred to as ACMG guidelines). The study has been approved by the Medical Ethics Committee of the Children′s Hospital Affiliated to Zhengzhou University (Ethics No.2022-K-L025). Results:The child was a 1-year-and-3-months-old boy whose parents were sib mating. The child presented with global developmental delay, microcephaly and short stature. MRI showed poor white matter myelination, abnormal signals of bilateral periventricular white matter and bilateral external sac, thin corpus callosum, and widening of the third ventricle. Genetic testing revealed that the TRAPPC6B gene of the child had a homozygous variant of c. 240_241delAA (p.Q80Hfs*34), which was inherited from his parents. According to the ACMG guidelines, this variant was judged to be potentially pathogenic (PVS1_Strong+ PM2_Supporting+ PM3_Supporting), resulting in premature occurrence of terminator codons and a change in the three-dimensional structure of protein. The variant was located in the functional domain, which may directly affect the functional domain of the protein, resulting in functional domain defects. Conclusion:The frameshift variation of TRAPPC6B gene c. 240_241delAA (p.Q80Hfs*34) has not been reported, which may be the genetic cause of neurodevelopmental disorders in child in this study. These findings expand the variation spectrum of TRAPPC6B gene and provid basis for genetic counseling and prenatal diagnosis of this family.

Objective:To explore the clinical characteristics and genetic etiology of a child with Osteopathia striata with cranial sclerosis (OSCS) due to variant of AMER1 gene. Methods:A child presented at the Affiliated Children′s Hospital of Zhengzhou University in July 2024 due to growth and development retardation was selected as the study subject. A retrospective study was conducted to collect the child′s clinical data. Peripheral blood samples (2 mL each) were collected from the child and her parents, and genomic DNA was extracted for whole exome sequencing (WES). Sanger sequencing was used for the verification of candidate variants. The pathogenicity of variant was rated according to the guidelines from American College of Medical Genetics and Genomics (ACMG). The study has been approved by the Medical Ethics Committee of the Children′s Hospital Affiliated to Zhengzhou University (Ethics No.: 2024-108-001).Results:The patient, a 4-year-and-10-month-old girl, presented with global developmental delay, short stature, cleft palate, distinct facial features, and hearing impairment. WES revealed that she has harbored a heterozygous c. 790_794dup (p.Cys265Trpfs*19) variant of the AMER1 gene, which was not detected in either parent. Based on the guidelines from ACMG, the gene variant was classified as pathogenic (PVS1 + PS2 + PM2_supporting). As the result of a non-triplet base insertion in the coding region of the AMER1 gene, it has converted a codon originally encoding an amino acid into a stop codon, and led to a truncated protein, causing severe alteration and dysfunction of the protein. Conclusion:The child was diagnosed with OSCS for clinical features such as global developmental delay, short stature, cleft palate, distinctive facial features, and hearing impairment, for which the de novo heterozygous frameshift variant AMER1: c. 790_794dup (p.Cys265Trpfs*19) may be accountable. Above finding has expanded the mutational spectrum of OSCS and provided a basis for genetic counseling and prenatal diagnosis for the family.

OBJECTIVE: To explore the clinical phenotype and genetic characteristics of a child with neurodevelopmental disorder caused by homozygous frameshift variant of the TRAPPC6B gene, and to provide reference for the diagnosis of the disease. METHODS: A child with neurodevelopmental disorder caused by homozygous variant of TRAPPC6B gene who was admitted to the Children's Hospital Affiliated to Zhengzhou University in March 2023 due to "inability to stand and walk independently at 1 year and 3 months old" was selected as the study object. The clinical data were collected by retrospective analysis method. Target region high-throughput sequencing was carried out on the child and parental peripheral blood samples, and candidate variant was verified by Sanger sequencing and bioinformatic analysis. The pathogenicity of variant was rated according to the Standards and Guidelines for the Interpretation of Sequence Variants released by American College of Medical Genetics and Genomics (ACMG) (hereinafter referred to as ACMG guidelines). The study has been approved by the Medical Ethics Committee of the Children's Hospital Affiliated to Zhengzhou University (Ethic No.2022-K-L025). RESULTS: The child was a 1-year-and-3-months-old boy whose parents were sib mating. The child presented with global developmental delay, microcephaly and short stature. MRI showed poor white matter myelination, abnormal signals of bilateral periventricular white matter and bilateral external sac, thin corpus callosum, and widening of the third ventricle. Genetic testing revealed that the TRAPPC6B gene of the child had a homozygous variant of c.240_241delAA (p.Q80Hfs*34), which was inherited from his parents. According to the ACMG guidelines, this variant was judged to be potentially pathogenic (PVS1_Strong+PM2_Supporting+PM3_Supporting), resulting in premature occurrence of terminator codons and a change in the three-dimensional structure of protein. The variant was located in the functional domain, which may directly affect the functional domain of the protein, resulting in functional domain defects. CONCLUSION The frameshift variation of TRAPPC6B gene c.240_241delAA (p.Q80Hfs*34) has not been reported, which may be the genetic cause of neurodevelopmental disorders in child in this study. These findings expand the variation spectrum of TRAPPC6B gene and provide basis for genetic counseling and prenatal diagnosis of this family.
Humans ; Infant ; Male ; Frameshift Mutation ; Homozygote ; Neurodevelopmental Disorders/genetics* ; Phenotype

OBJECTIVE: To explore the clinical phenotypes and genetic characteristics of a pedigree with Distal arthrogryposis type 5D (DA5D) caused by compound heterozygous variants in the ECEL1 gene. METHODS: A child (proband) diagnosed with DA5D and his family members (proband's parents and sister) who was admitted to the Department of Rehabilitation Medicine of Henan Children's Hospital in July 2022 due to "multiplex distal arthrogryposis" were enrolled into this study. Clinical data of the proband were collected and peripheral blood samples were obtained from the proband and members of his family about 3 mL. Trio-whole genome sequencing (trio-WGS) was carried out to detected the genetic variations of the proband and his family members. The candidate's pathogenic gene variants were screened and analyzed by Genome Aggregation Database (gnomAD) and other databases. The screened variants were annotated for clinical phenotypes using databases like the Online Mendelian Inheritance in Man (OMIM). The pathogenicity of the candidate variants was predicted by bioinformatics tools such as Provean. Based on the guidelines of the American College of Medical Genetics and Genomics (ACMG), pathogenicity ratings were conducted for variant sites. The protein conservation and mutation structure prediction of ECEL1 protein among species were carried out though MEGA-X and PyMOL. The research protocol of this study was reviewed by the Ethics Committee of Henan Provincial Children's Hospital (Approval No. 2023-H-H01), and informed consent for clinical research was obtained from the guardians of the probands. RESULTS: The proband had multiplex distal arthrogryposis involving hands, feet, knees, and ankles, and had right ptosis, micrognathia, low auricular position, and upturned nose. The parents and sister both had normal phenotypes. Trio-WGS and Sanger sequencing revealed that the child had compound heterozygous variants of paternal c.1742_c.1743insT and maternal c.2314T>G, for which the father and sister were carriers of the c.1742_c.1743insT heterozygous variant and the mother was carrier of c.2314T>A. Neither mutation site has been reported. According to guidelines of ACMG, the c.1742_c.1743insT variant was classified as likely pathogenic (PSV1+PM2_Supporting), and c.2314T>G was classified as uncertain (PM2_Supporting+PM3+PP3). The results of conserved analysis of amino acid residue sequences of ECEL1 protein showed that the missense mutation of the maternal c.2314T>G (p.Cys772Gly) was highly conserved among humans and other seven species. The protein structure prediction revealed that the c.1742_c.1743insT frameshift mutation led to the protein truncation, and the c.2314T>G missense mutation resulted in the failure of forming 1 disulfide bond. CONCLUSION The compound heterozygous variants of ECEL1 gene were considered to be pathogenic for this DA5D patient, which have expanded the mutational spectrum of the ECEL1 gene and provided a reference for clinical diagnosis as well as genetic counseling for this family.
Humans ; Pedigree ; Arthrogryposis/genetics* ; Male ; Female ; Heterozygote ; Phenotype ; Mutation ; Child ; Metalloendopeptidases

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a child with Osteopathia striata with cranial sclerosis (OSCS) due to variant of AMER1 gene. METHODS: A child presented at the Affiliated Children's Hospital of Zhengzhou University in July 2024 due to growth and development retardation was selected as the study subject. A retrospective study was conducted to collect the child's clinical data. Peripheral blood samples (2 mL each) were collected from the child and her parents, and genomic DNA was extracted for whole exome sequencing (WES). Sanger sequencing was used for the verification of candidate variants. The pathogenicity of variant was rated according to the guidelines from American College of Medical Genetics and Genomics (ACMG). The study has been approved by the Medical Ethics Committee of the Children's Hospital Affiliated to Zhengzhou University (Ethics No.: 2024-108-001). RESULTS: The patient, a 4-year-and-10-month-old girl, presented with global developmental delay, short stature, cleft palate, distinct facial features, and hearing impairment. WES revealed that she has harbored a heterozygous c.790_794dup (p.Cys265Trpfs*19) variant of the AMER1 gene, which was not detected in either parent. Based on the guidelines from ACMG, the gene variant was classified as pathogenic (PVS1 + PS2 + PM2_supporting). As the result of a non-triplet base insertion in the coding region of the AMER1 gene, it has converted a codon originally encoding an amino acid into a stop codon, and led to a truncated protein, causing severe alteration and dysfunction of the protein. CONCLUSION The child was diagnosed with OSCS for clinical features such as global developmental delay, short stature, cleft palate, distinctive facial features, and hearing impairment, for which the de novo heterozygous frameshift variant AMER1: c.790_794dup (p.Cys265Trpfs*19) may be accountable. Above finding has expanded the mutational spectrum of OSCS and provided a basis for genetic counseling and prenatal diagnosis for the family.
Humans ; Female ; Child, Preschool ; Osteosclerosis/genetics* ; Adaptor Proteins, Signal Transducing/genetics* ; Mutation ; Exome Sequencing ; Retrospective Studies ; Tumor Suppressor Proteins

Objective:To explore the clinical phenotypes and genetic characteristics of a pedigree with Distal arthrogryposis type 5D (DA5D) caused by compound heterozygous variants in the ECEL1 gene. Methods:A child (proband) diagnosed with DA5D and his family members (proband′s parents and sister) who was admitted to the Department of Rehabilitation Medicine of Henan Children′s Hospital in July 2022 due to " multiplex distal arthrogryposis" were enrolled into this study. Clinical data of the proband were collected and peripheral blood samples were obtained from the proband and members of his family about 3 mL. Trio-whole genome sequencing (trio-WGS) was carried out to detected the genetic variations of the proband and his family members. The candidate′s pathogenic gene variants were screened and analyzed by Genome Aggregation Database (gnomAD) and other databases. The screened variants wer annotated for clinical phenotypes using databases like the Online Mendelian Inheritance in Man (OMIM). The pathogenicity of the candidate variants was predicted by bioinformatics tools such as Provean. Based on the guidelines of the American College of Medical Genetics and Genomics (ACMG), pathogenicity ratings were conducted for variant sites. The protein conservation and mutation structure prediction of ECEL1 protein among species were carried out though MEGA-X and PyMOL. The research protocol of this study was reviewed by the Ethics Committee of Henan Provincial Children′s Hospital (Approval No. 2023-H-H01), and informed consent for clinical research was obtained from the guardians of the probands.Results:The proband had multiplex distal arthrogryposis involving hands, feet, knees, and ankles, and had right ptosis, micrognathia, low auricular position, and upturned nose. The parents and sister both had normal phenotypes. Trio-WGS and Sanger sequencing revealed that the child had compound heterozygous variants of paternal c. 1742_c.1743insT and maternal c. 2314T>G, for which the father and sister were carriers of the c. 1742_c.1743insT heterozygous variant and the mother was carrier of c. 2314T>A. Neither mutation site has been reported. According to guidelines of ACMG, the c. 1742_c.1743insT variant was classified as likely pathogenic (PSV1+ PM2_Supporting), and c. 2314T>G was classified as uncertain (PM2_Supporting+ PM3+ PP3). The results of conserved analysis of amino acid residue sequences of ECEL1 protein showed that the missense mutation of the maternal c. 2314T>G(p.Cys772Gly) was highly conserved among humans and other seven species. The protein structure prediction revealed that the c.1742_c.1743insT frameshift mutation led to the protein truncation, and the c. 2314T>G missense mutation resulted in the failure of forming 1 disulfide bond.Conclusion:The compound heterozygous variants of ECEL1 gene were considered to be pathogenic for this DA5D patient, which have expanded the mutational spectrum of the ECEL1 gene and provided a reference for clinical diagnosis as well as genetic counseling for this family.

Objective:To explore the clinical phenotype and genetic characteristics of a child with neurodevelopmental disorder caused by homozygous frameshift variant of the TRAPPC6B gene, and to provide reference for the diagnosis of the disease. Methods:A child with neurodevelopmental disorder caused by homozygous variant of TRAPPC6B gene who was admitted to the Children′s Hospital Affiliated to Zhengzhou University in March 2023 due to " inability to stand and walk independently at 1 year and 3 months old" was selected as the study object. The clinical data were collected by retrospective analysis method. Target region high-throughput sequencing was carried out on the child and parental peripheral blood samples, and candidate variant was verified by Sanger sequencing and bioinformatic analysis. The pathogenicity of variant was rated according to the Standards and Guidelines for the Interpretation of Sequence Variants released by American College of Medical Genetics and Genomics (ACMG) (hereinafter referred to as ACMG guidelines). The study has been approved by the Medical Ethics Committee of the Children′s Hospital Affiliated to Zhengzhou University (Ethics No.2022-K-L025). Results:The child was a 1-year-and-3-months-old boy whose parents were sib mating. The child presented with global developmental delay, microcephaly and short stature. MRI showed poor white matter myelination, abnormal signals of bilateral periventricular white matter and bilateral external sac, thin corpus callosum, and widening of the third ventricle. Genetic testing revealed that the TRAPPC6B gene of the child had a homozygous variant of c. 240_241delAA (p.Q80Hfs*34), which was inherited from his parents. According to the ACMG guidelines, this variant was judged to be potentially pathogenic (PVS1_Strong+ PM2_Supporting+ PM3_Supporting), resulting in premature occurrence of terminator codons and a change in the three-dimensional structure of protein. The variant was located in the functional domain, which may directly affect the functional domain of the protein, resulting in functional domain defects. Conclusion:The frameshift variation of TRAPPC6B gene c. 240_241delAA (p.Q80Hfs*34) has not been reported, which may be the genetic cause of neurodevelopmental disorders in child in this study. These findings expand the variation spectrum of TRAPPC6B gene and provid basis for genetic counseling and prenatal diagnosis of this family.