Objective:To assess the value of whole exome sequencing (WES) for the diagnosis of early-onset genetic diseases among infants aged 0 to 6 month in Ningbo region.Methods:268 infants presented at the Women and Children′s Hospital Affiliated to Ningbo University from January 2022 to June 2024 undergoing WES-based genetic testing were enrolled. Peripheral blood samples were collected from the infants and their parents and subjected to WES. Pathogenic variants were identified by clinical manifestations. This study has been approved by the Medical Ethics Committee of the Hospital (Ethics No. EC2023-017).Results:Among the 268 infants, 124 (46.3%) had phenotype-explaining genetic variants. For 42 family-based WES tests, 20 (47.62%) were abnormal, whilst in 226 single-person WES tests, 104 (46.02%) had abnormalities, with 76 (33.63%) verified by parental testing. In 96 fully family-verified cases, 31 were de novo, 40 were parent-inherited, 25 were single-parent-inherited. These included 35 inborn metabolic errors, 28 rare syndromes, 9 neurodevelopmental disorders, 4 musculoskeletal diseases, 5 congenital deafness, 2 mitochondrial diseases, 4 endocrine diseases, and 9 others. Among these, there were 7 pathogenic copy number variations (all deletions), 3 chromosomal abnormalities, and 85 single-nucleotide variations. One case of Beckwith-Wiedemann syndrome was detected by methylation MLPA. Among the single-nucleotide variants, 114 pathogenic/likely pathogenic variants were identified in 61 genes, with common ones including missense variants (64.04%), frameshifting variants (20.18%) and splicing variants (4.39%). Conclusion:WES can offer effective diagnosis for hereditary diseases with specific/non-specific manifestations. For early-age infants, higher detection rates may be attained for inborn metabolic errors, rare syndromes, neurodevelopmental disorders, congenital deafness, and musculoskeletal diseases. Compared with single-person WES, family-based WES can attain a higher diagnostic efficiency.

Objective:To determine the prevalence of GJB2 gene c. 109G>A (p.V37I) variant among infants with congenital hearing loss and analyze the initial audiological characteristics of children harboring the variant, compare the audiometric difference among individuals with various genotypes, and explore genetic and audiological manifestations of the affected families. Methods:One hundred twenty six infants diagnosed with congenital hearing loss at the Neonate Screening Center of Ningbo City from June 2021 to December 2024 were selected as the study subjects. The neonates, in addition with members from 16 of their families, had undergone genetic screening for variants of 208 hotspot sites within 24 deafness-associated genes. For cases identified with monoallelic variants and concurrent hearing loss, the full GJB2 gene was sequenced. Meanwhile, a retrospective analysis was carried out on 23 children whom were confirmed to have hearing loss and the c. 109G>A variant by whole exome sequencing from March 2022 to December 2024. And 102 children who were excluded to have hearing loss and pathogenic variants by whole exome sequencing were selected as normal controls. Audiological features of individuals harboring the c. 109G>A variant were compared. This study has been approved by the Medical Ethics Committee of The Affiliated Women and Children′s Hospital of Ningbo University (Ethics No.: EC2023-009). Results:For the 126 infants with congenital hearing loss, prospective screening has identified 58 (46.03%) to harbor the c. 109G>A variant. These included 38 homozygotes and 16 compound heterozygotes. Retrospective review of the 23 c. 109G>A positive children has identified 15 as homozygotes and 8 as compound heterozygotes. Genetic testing of the 16 pedigrees has identified 7 homozygotes and 1 compound heterozygote. For the homozygotes combined ( n=53), 96.2% exhibited bilateral symmetric hearing loss, with 78.3% showing high-frequency sloping patterns, and 98.1% having a hearing threshold ranging from 20 to 65 dB. For the compound heterozygotes combined ( n=24), 95.8% showed symmetric loss, with 59.4% having high-frequency sloping, and 97.9% had a hearing threshold ranging from 20 to 65 dB. Both groups showed significantly elevated ABR/PTA thresholds compared with the normal controls ( P=0.000). The compound heterozygous group had higher ABR thresholds (43.3 ± 15.0 dB nHL) compared with the homozygous group (39.1±12.0 dB nHL, P=0.005). Conclusion:Infants harboring the GJB2 c. 109G>A variant primarily manifest as mild-to-moderate, symmetric, high-frequency sloping hearing loss. Nearly one-third of affected children have thresholds between 20 to 35 dB nHL, suggesting that ABR > 35 dB nHL alone may underestimate the hearing impairment in this population. Compared with homozygotes, compound heterozygotes with the the GJB2 c. 109G>A variant can confer a more severe hearing loss.

OBJECTIVE: To assess the value of whole exome sequencing (WES) for the diagnosis of early-onset genetic diseases among infants aged 0 to 6 month in Ningbo region. METHODS: 268 infants presented at the Women and Children's Hospital Affiliated to Ningbo University from January 2022 to June 2024 undergoing WES-based genetic testing were enrolled. Peripheral blood samples were collected from the infants and their parents and subjected to WES. Pathogenic variants were identified by clinical manifestations. This study has been approved by the Medical Ethics Committee of the Hospital (Ethics No. EC2023-017). RESULTS: Among the 268 infants, 124 (46.3%) had phenotype-explaining genetic variants. For 42 family-based WES tests, 20 (47.62%) were abnormal, whilst in 226 single-person WES tests, 104 (46.02%) had abnormalities, with 76 (33.63%) verified by parental testing. In 96 fully family-verified cases, 31 were de novo, 40 were parent-inherited, 25 were single-parent-inherited. These included 35 inborn metabolic errors, 28 rare syndromes, 9 neurodevelopmental disorders, 4 musculoskeletal diseases, 5 congenital deafness, 2 mitochondrial diseases, 4 endocrine diseases, and 9 others. Among these, there were 7 pathogenic copy number variations (all deletions), 3 chromosomal abnormalities, and 85 single-nucleotide variations. One case of Beckwith-Wiedemann syndrome was detected by methylation MLPA. Among the single-nucleotide variants, 114 pathogenic/likely pathogenic variants were identified in 61 genes, with common ones including missense variants (64.04%), frameshifting variants (20.18%) and splicing variants (4.39%). CONCLUSION WES can offer effective diagnosis for hereditary diseases with specific/non-specific manifestations. For early-age infants, higher detection rates may be attained for inborn metabolic errors, rare syndromes, neurodevelopmental disorders, congenital deafness, and musculoskeletal diseases. Compared with single-person WES, family-based WES can attain a higher diagnostic efficiency.
Humans ; Exome Sequencing/methods* ; Infant ; Female ; Male ; Infant, Newborn ; Genetic Diseases, Inborn/diagnosis* ; Genetic Testing/methods*

OBJECTIVE: To determine the prevalence of GJB2 gene c.109G>A (p.V37I) variant among infants with congenital hearing loss and analyze the initial audiological characteristics of children harboring the variant, compare the audiometric difference among individuals with various genotypes, and explore genetic and audiological manifestations of the affected families. METHODS: One hundred twenty six infants diagnosed with congenital hearing loss at the Neonate Screening Center of Ningbo City from June 2021 to December 2024 were selected as the study subjects. The neonates, in addition with members from 16 of their families, had undergone genetic screening for variants of 208 hotspot sites within 24 deafness-associated genes. For cases identified with monoallelic variants and concurrent hearing loss, the full GJB2 gene was sequenced. Meanwhile, a retrospective analysis was carried out on 23 children whom were confirmed to have hearing loss and the c.109G>A variant by whole exome sequencing from March 2022 to December 2024. And 102 children who were excluded to have hearing loss and pathogenic variants by whole exome sequencing were selected as normal controls. Audiological features of individuals harboring the c.109G>A variant were compared. This study has been approved by the Medical Ethics Committee of The Affiliated Women and Children's Hospital of Ningbo University (Ethics No.: EC2023-009). RESULTS: For the 126 infants with congenital hearing loss, prospective screening has identified 58 (46.03%) to harbor the c.109G>A variant. These included 38 homozygotes and 16 compound heterozygotes. Retrospective review of the 23 c.109G>A positive children has identified 15 as homozygotes and 8 as compound heterozygotes. Genetic testing of the 16 pedigrees has identified 7 homozygotes and 1 compound heterozygote. For the homozygotes combined (n = 53), 96.2% exhibited bilateral symmetric hearing loss, with 78.3% showing high-frequency sloping patterns, and 98.1% having a hearing threshold ranging from 20 to 65 dB. For the compound heterozygotes combined (n = 24), 95.8% showed symmetric loss, with 59.4% having high-frequency sloping, and 97.9% had a hearing threshold ranging from 20 to 65 dB. Both groups showed significantly elevated ABR/PTA thresholds compared with the normal controls (P = 0.000). The compound heterozygous group had higher ABR thresholds (43.3 ± 15.0 dB nHL) compared with the homozygous group (39.1 ± 12.0 dB nHL, P = 0.005). CONCLUSION Infants harboring the GJB2 c.109G>A variant primarily manifest as mild-to-moderate, symmetric, high-frequency sloping hearing loss. Nearly one-third of affected children have thresholds between 20 to 35 dB nHL, suggesting that ABR > 35 dB nHL alone may underestimate the hearing impairment in this population. Compared with homozygotes, compound heterozygotes with the the GJB2 c.109G>A variant can confer a more severe hearing loss.
Humans ; Connexin 26/genetics* ; Female ; Male ; Infant, Newborn ; Infant ; Hearing Loss/genetics* ; Retrospective Studies ; Child, Preschool ; Child ; Genotype ; Connexins/genetics* ; Mutation

Objective:To assess the value of whole exome sequencing (WES) for the diagnosis of early-onset genetic diseases among infants aged 0 to 6 month in Ningbo region.Methods:268 infants presented at the Women and Children′s Hospital Affiliated to Ningbo University from January 2022 to June 2024 undergoing WES-based genetic testing were enrolled. Peripheral blood samples were collected from the infants and their parents and subjected to WES. Pathogenic variants were identified by clinical manifestations. This study has been approved by the Medical Ethics Committee of the Hospital (Ethics No. EC2023-017).Results:Among the 268 infants, 124 (46.3%) had phenotype-explaining genetic variants. For 42 family-based WES tests, 20 (47.62%) were abnormal, whilst in 226 single-person WES tests, 104 (46.02%) had abnormalities, with 76 (33.63%) verified by parental testing. In 96 fully family-verified cases, 31 were de novo, 40 were parent-inherited, 25 were single-parent-inherited. These included 35 inborn metabolic errors, 28 rare syndromes, 9 neurodevelopmental disorders, 4 musculoskeletal diseases, 5 congenital deafness, 2 mitochondrial diseases, 4 endocrine diseases, and 9 others. Among these, there were 7 pathogenic copy number variations (all deletions), 3 chromosomal abnormalities, and 85 single-nucleotide variations. One case of Beckwith-Wiedemann syndrome was detected by methylation MLPA. Among the single-nucleotide variants, 114 pathogenic/likely pathogenic variants were identified in 61 genes, with common ones including missense variants (64.04%), frameshifting variants (20.18%) and splicing variants (4.39%). Conclusion:WES can offer effective diagnosis for hereditary diseases with specific/non-specific manifestations. For early-age infants, higher detection rates may be attained for inborn metabolic errors, rare syndromes, neurodevelopmental disorders, congenital deafness, and musculoskeletal diseases. Compared with single-person WES, family-based WES can attain a higher diagnostic efficiency.

Objective:To determine the prevalence of GJB2 gene c. 109G>A (p.V37I) variant among infants with congenital hearing loss and analyze the initial audiological characteristics of children harboring the variant, compare the audiometric difference among individuals with various genotypes, and explore genetic and audiological manifestations of the affected families. Methods:One hundred twenty six infants diagnosed with congenital hearing loss at the Neonate Screening Center of Ningbo City from June 2021 to December 2024 were selected as the study subjects. The neonates, in addition with members from 16 of their families, had undergone genetic screening for variants of 208 hotspot sites within 24 deafness-associated genes. For cases identified with monoallelic variants and concurrent hearing loss, the full GJB2 gene was sequenced. Meanwhile, a retrospective analysis was carried out on 23 children whom were confirmed to have hearing loss and the c. 109G>A variant by whole exome sequencing from March 2022 to December 2024. And 102 children who were excluded to have hearing loss and pathogenic variants by whole exome sequencing were selected as normal controls. Audiological features of individuals harboring the c. 109G>A variant were compared. This study has been approved by the Medical Ethics Committee of The Affiliated Women and Children′s Hospital of Ningbo University (Ethics No.: EC2023-009). Results:For the 126 infants with congenital hearing loss, prospective screening has identified 58 (46.03%) to harbor the c. 109G>A variant. These included 38 homozygotes and 16 compound heterozygotes. Retrospective review of the 23 c. 109G>A positive children has identified 15 as homozygotes and 8 as compound heterozygotes. Genetic testing of the 16 pedigrees has identified 7 homozygotes and 1 compound heterozygote. For the homozygotes combined ( n=53), 96.2% exhibited bilateral symmetric hearing loss, with 78.3% showing high-frequency sloping patterns, and 98.1% having a hearing threshold ranging from 20 to 65 dB. For the compound heterozygotes combined ( n=24), 95.8% showed symmetric loss, with 59.4% having high-frequency sloping, and 97.9% had a hearing threshold ranging from 20 to 65 dB. Both groups showed significantly elevated ABR/PTA thresholds compared with the normal controls ( P=0.000). The compound heterozygous group had higher ABR thresholds (43.3 ± 15.0 dB nHL) compared with the homozygous group (39.1±12.0 dB nHL, P=0.005). Conclusion:Infants harboring the GJB2 c. 109G>A variant primarily manifest as mild-to-moderate, symmetric, high-frequency sloping hearing loss. Nearly one-third of affected children have thresholds between 20 to 35 dB nHL, suggesting that ABR > 35 dB nHL alone may underestimate the hearing impairment in this population. Compared with homozygotes, compound heterozygotes with the the GJB2 c. 109G>A variant can confer a more severe hearing loss.

Objective:To investigate the pathogenic spectrum of children with severe infection by metagenomic next generation sequencing (mNGS).Methods:This study was a cross-sectional study. We collected 212 cases of severely infected pediatric patients admitted to the Intensive Care Unit (ICU) of the Women and Children′s Hospital of Ningbo University from January 2022 to June 2023, and performed metagenomic next-generation sequencing (mNGS) on 249 samples to analyze the pathogenic distribution characteristics.Results:Among the 249 samples of 212 children, the positive detection rate was 49.80% (124/249), including 14 cases of mixed infections, accounting for 6.60% (14/212). According to the mNGS technology, the pathogen distribution of severely infected children showed that the most common Gram-positive bacteria were Staphylococcus aureus (3.61%, 9/249), Streptococcus pneumoniae (2.81%, 7/249), and Staphylococcus epidermidis (2.41%, 6/249); the most common Gram-negative bacteria were Klebsiella aerogenes (2.41%, 6/249), Klebsiella pneumoniae (2.41%, 6/249), and Haemophilus parainfluenzae (2.01%, 5/249). The most common fungus was Candida parapsilosis (2.01%, 5/249). The most common virus was Human Cytomegalovirus (HCMV) (6.02%, 15/249), Human Herpesvirus 1 (HHV-1) (1.61%, 4/249), and Epstein-Barr virus (EBV) (1.61%, 4/249). The most common atypical pathogen was Mycoplasma pneumoniae (3.21%, 8/249). Conclusions:This study explored the pathogen spectrum in severely infected pediatric patients through mNGS, contributing to the diagnosis of mixed infections or infections caused by uncommon or rare pathogens, which enables rapid and efficient identification of pathogens.

Objective:To explore the clinical characteristics and genetic etiology of four children with Phelan-McDermid syndrome (PMS).Methods:Four children who had visited the Affiliated Women and Children′s Hospital of Ningbo University between June 2, 2022 and May 8, 2023 were selected as the study subjects. Clinical data of the children were collected. Genomic DNA was extracted from peripheral blood samples of the children and their parents and subjected to whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing and quantitative PCR (q-PCR) analysis. This study was approved by the Medical Ethics Committee of the Affiliated Women and Children′s Hospital of Ningbo University (Ethics No. EC2020-048).Results:All children had presented with speech and language delays and intellectual disability. Children 3 and 4 also presented with autistic behaviors. WES showed that the children 1 and 2 had respectively carried a heterozygous c.731T>C (p.Leu244Pro) and a c.2782_2851del (p.Gly928ArgfsTer4) variant of the SHANK3 gene. Sanger sequencing confirmed that their parents did not carry the same variant, suggesting that they were de novo in origin. Children 3 and 4 had respectively harbored a 121 kb and 52.02 kb heterozygous deletion at chromosome 22q13.33, which had both encompassed the SHANK3 and ACR genes mapped to 22q13.33. q-PCR results showed that the deletion of SHANK3 and ACR genes were de novo in origin. Based on the guidelines from the American College of Medical Genetics and Genomics, the c. 731T>C and c. 2782_2851del variants were predicted to be likely pathogenic (PS2+ PM2_Supporting+ PP3) and pathogenic (PVS1+ PM2_Supporting+ PS2_Supporting), respectively. Furthermore, the 52.02 kb and 121 kb heterozygous deletions in 22q13.33 were both predicted to be pathogenic (2D+ 4C, 1.05 in score; 2D+ 4C, 1 in score). Conclusion:The four children were all diagnosed with PMS by genetic testing. Above finding has enriched the phenotypic and mutational spectrum of PMS, and provided a basis for clinical diagnosis and genetic counseling for their families.

OBJECTIVE: To explore the clinical characteristics and genetic etiology for two children with Neurodevelopmental disorder with hypotonia, stereotypic hand movements, and impaired language (MEDHSIL). METHODS: Two children who had visited the Ningbo Women and Children's Hospital on October 15, 2021 were selected as the study subjects. Whole exome sequencing (WES) was carried out for both patients. Candidate variants were verified by Sanger sequencing of their family members. RESULTS: The two children were respectively found to harbor a heterozygous c.138delC (p.Ile47Serfs*42) variant and a c.833del (p.L278*) variant of the MEF2C gene. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were predicted to be pathogenic (PVS1+PS2+PM2_Supporting). CONCLUSION The c.138delC and c.833del variants of the MEF2C gene probably underlay the pathogenesis of MEDHSIL in the two children. Above findings have enriched the mutational spectrum of the MEF2C gene and enabled genetic counseling for their families.
Child ; Humans ; Family ; Genetic Counseling ; Language ; MEF2 Transcription Factors/genetics* ; Muscle Hypotonia/genetics* ; Neurodevelopmental Disorders

OBJECTIVE: To explore the types of NF1 gene variants and clinical characteristics among patients with Neurofibromatosis type I (NF1). METHODS: Clinical data of 12 patients diagnosed at Ningbo Women and Children's Hospital between December 2019 and May 2022 were retrospectively analyzed. The probands and their family members were subjected to high-throughput sequencing, and candidate variants were verified by Sanger sequencing and chromosome microarray analysis. RESULTS: The 12 patients had ranged from 4 months to 27 years old, with a male-to-female ratio of 2 : 1. Cafè-au-lait spots were found in all patients. 83.3% of them also had axillary and/or inguinal freckling, 58.3% had neurofibromas, and 16.7% had congenital pseudarthrosis of the tibia. Five types of NF1 gene variants were identified in the patients, including 5 nonsense variants, 4 frameshift variants, 1 missense variant, 1 splice variant, 1 large deletion involving the whole gene. Six patients were found to harbor de novo variants, 2 had inherited the variants from their parents, and 4 were not verified for their parental origin. The c.3379del (p.Thr1127Glnfs*15) and c.6628_6629del (p.Glu2210Thrfs*10) variants were unreported in literature and databases. CONCLUSION Most NF1 patients may present with Cafè-au-lait spots initially and are due to pathogenic variant of the NF1 gene. High-throughput sequencing can efficiently identify such variants among the patients and enable the definite diagnosis.
Child ; Humans ; Female ; Male ; Neurofibromatosis 1/diagnosis* ; Cafe-au-Lait Spots/diagnosis* ; Genes, Neurofibromatosis 1 ; Retrospective Studies ; Frameshift Mutation