OBJECTIVE: To explore the genetic variants and phenotypic characteristics of patients with Neurofibromatosis type I (NF1). METHODS: Twenty two NF1 patients who presented at Enze Medical (Center) Group in Taizhou between 2018 and 2024 were selected as the study subjects. Clinical phenotype and family history were collected for the patients. Whole exome sequencing (WES) was carried out for the 22 probands to screen the variants of NF1 gene. Candidate variants were verified by Sanger sequencing of their family members. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: K20230902). RESULTS: The 22 probands were diagnosed between the age of 5 months to 47 years old, and have all shown cafe au lait spots on their skin. Seventeen patients exhibited the phenotype at birth, and 11 had various degrees of neurofibromatosis. Among them, probands 1 and 13 underwent surgical resection of the tumor but had recurred, while proband 12 had amputation due to the huge size and serious impact of the neurofibroma and had no recurrence. Five patients had various degrees of scoliosis. In total 22 germline mutations and one somatic mutation were identified among the 22 families, with 5 variants unreported previously, including 1 nonsense mutation c.1603C>T (Q535*), 3 frameshift mutations [c.7268_7269delCA (Thr2423fs), c.2293del (Arg765Alafs*26), and c.5433_5438delinsGC (Phe1812ArgfsTer50)], and 1 deletion involving exons 41-44 of the NF1 gene and adjacent introns. Proband 13 was found to harbor germline mutation c.6796C>T (Gln2266Ter) and somatic mutation c.1019_1020del (Ser340Cysfs Ter12) in the peripheral blood and tumor tissue, respectively. Among the 22 NF1 probands, 6 had received treatment due to severe illness. Proband 1 had tumor resection in the right upper limb, but was found to have malignant lung tumor and died during follow-up. Proband 12 had multiple recurrence of neurofibroma in the left ring finger. Proband 4 underwent spinal correction surgery due to severe scoliosis. Proband 11 had died due to a central nervous system disease. Among the 22 germline mutations, 6 had led to the occurrence of truncated proteins, which may have a more severe impact on the phenotype. CONCLUSION This study investigated the genetic variants and clinical phenotypes of 22 NF1 families and identified 5 novel variants of the NF1 gene, which has expanded the genotypic and phenotypic spectra of the NF1. Preliminary studies have identified an association between truncated mutations, young age, and severe phenotypes, which may provide important clues for prognosis evaluation. For the clinical diagnosis and treatment of NF1, it is necessary to consider the phenotypic characteristics and genetic testing in combination with genetic counseling and long-term follow-up.
Humans ; Neurofibromatosis 1/pathology* ; Male ; Female ; Pedigree ; Adult ; Child ; Child, Preschool ; Middle Aged ; Adolescent ; Infant ; Young Adult ; Neurofibromin 1/genetics* ; Phenotype ; Asian People/genetics* ; Mutation ; Exome Sequencing ; East Asian People

OBJECTIVE: To explore the genetic testing outcomes of a fetal family with Thyroid dyshormonogenesis type 5 (TDH5) and familial Neurofibromatosis type 1 (NF1), and to clarify the association between clinical manifestations and genetic variations. METHODS: One case of a TDH5 combined with familiar NF1 fetus treated at Gansu Maternal and Child Health Hospital in January 2024 was selected as the research subject. The clinical and family history data of the fetus were collected by retrospective research method. 10-15 mL of fetal amniotic fluid, and 2-3 mL of peripheral blood from the parents, sister, and grandfather of the fetus were collected, and genomic DNA was extracted for trio whole-exome sequencing (trio-WES). The Sanger sequencing was utilized to validate candidate variants for family verification. According to the Standards and Guidelines for the Interpretation and Reporting of Sequence Variants of the American Society of Medical Genetics and Genomics (ACMG) (hereafter referred to as the ACMG guidelines), the pathogenicity of the detected variants was classified. This study has been approved by the Medical Ethics Committee of Gansu Maternal and Child Health Hospital [Ethics No.（2021）GSFY（65）]. RESULTS: The fetal ultrasound indicated the nuchal translucency (NT) thickening, and the thyroid function test results of the sister showed an increase in thyroid stimulating hormone and a decrease in free thyroid hormone. Simultaneously, there were cafe-au-lait macules of various sizes in multiple parts of the body of the sister, and the mother had a similar cafe-au-lait macules phenotype. The trio-WES results revealed that there was a c.413dupA (p.Tyr138*) frameshift mutation in exon4 and c.573G>A (p.Trp191*) nonsense mutation in exon5 of the fetal DUOXA2, which were inherited from the mother and father, respectively. In accordance with the ACMG guidelines, they were classified as pathogenic variant (PVS1+PM2_Supporting+PM3) and likely pathogenic variant (PVS1+PM2_Supporting), respectively. And the nonsense mutation c.6972C>A (p.Tyr2264*) was detected in exon46 of the NF1 in the fetus, inherited from the mother maternal grandfather. The genetic testing results of the first sister and proband in this case were consistent, and the DUOXA2 and NF1 of the second sister were both wild-type. According to the ACMG guidelines, c.6972C>A (p.Tyr2264 *) was classified as pathogenic variant (PVS1+PS4_Supporting+PP4+PM2_Supporting). CONCLUSION The mutations in the DUOXA2 gene c.413dupA (p.Tyr138*) and c.573G>A (p.Trp191*), and the NF1 gene c.6972C>A (p.Tyr2264*) might be the genetic causes of TDH5 combined with familiar NF1 in proband. The discovery of the DUOXA2 gene c.573G>A (p.Trp191*) enriches the spectrum of pathogenic gene variations.
Humans ; Female ; Pedigree ; Pregnancy ; Neurofibromatosis 1/complications* ; Male ; Genetic Testing ; Adult ; Thyroid Dysgenesis/genetics* ; Fetus ; Exome Sequencing ; Mutation

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a child with Neurofibromatosis-Noonan syndrome (NFNS). METHODS: A child with NFNS who was treated at the Department of Endocrinology of Hangzhou Children's Hospital in January 2024 was selected as the study subject. Clinical data of the child was collected by retrospective analysis. Peripheral venous blood samples (2 mL each) were collected from the child and his parents. Genomic DNA was extracted, and trio-whole exome sequencing (Trio-WES) of the family was carried out. Sanger sequencing was used to perform family verification on the candidate variants. The identified variants were classified for pathogenicity according to the Standards and Guidelines for the Interpretation of Sequence Variants established by the American College of Medical Genetics and Genomics (ACMG) (hereafter referred to as the "ACMG guidelines"). This study has been approved by the Medical Ethics Committee of Hangzhou Children's Hospital (Ethics No. 2021-06). RESULTS: The child was a 7-year and 4-month-old male. He has short stature, numerous café-au-lait spots on the neck and trunk, and special facial features such as a full forehead, wide interpupillary distance, a low nasal bridge, and low-set ears. The results of Trio-WES showed that the he had harbored the NF1 gene c.3773G>T (p.W1258L) mutation, which was verified by Sanger sequencing to be de novo in origin. The NF1 gene was associated with NFNS, which has an autosomal dominant inheritance. According to the ACMG guidelines, this variant was judged to be a likely pathogenic variant (PS2+PM2+PP3+PP2). No pathogenic variant in genes associated with Noonan syndrome, such as PTPN11, SOS1, RAF1, RIT1, and KRAS, was found. CONCLUSION The child with NFNS has clinical features such as short stature, special facial features, and café-au-lait spots. The c.3773G>T (p.W1258L) variation in the NF1 gene may be the genetic etiology of the NFNS child in this study. The results of this study has enriched the variation spectrum of the NF1 gene.
Child ; Humans ; Male ; Exome Sequencing ; Mutation ; Neurofibromatosis 1/genetics* ; Neurofibromin 1/genetics* ; Noonan Syndrome/genetics*

OBJECTIVE: To explore the genetic basis for a child with café-au-lait macules and juvenile xanthogranuloma. METHODS: Clinical data and peripheral blood samples of the patient and her family members were collected and subjected to targeted capture and high-throughput sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: A deletional variant in exon 23 of the NF1 gene was detected in the proband. Sanger sequencing has verified it as a de novo variant, which was highly correlated with the clinical manifestations of the patient and her mother. The diagnosis of neurofibromatosis 1 (NF1) was established. The variant was unreported previously. CONCLUSION Targeted capture and next-generation sequencing combined with Sanger sequencing can facilitate early diagnosis of NF1 and provide a basis for the clinical treatment, genetic counseling and prenatal diagnosis.
Child ; Female ; Humans ; Cafe-au-Lait Spots/genetics* ; Genes, Neurofibromatosis 1 ; Neurofibromatosis 1/genetics* ; Xanthogranuloma, Juvenile/genetics*

OBJECTIVE: To explore the genetic basis for two children with sporadic neurofibromatosis type 1 (NF1) complicated with nephrotic syndrome (NS). METHODS: Clinical data of the children were collected. Both children were subjected to high-throughput sequencing, and candidate variants were verified by Sanger sequencing. RESULTS: Both children had café-au-lait macules, subaxillary freckle and Lisch nodules. Child 1 also had congenital tibiofibular pseudarthrosis on the left side. Genetic testing revealed that child 1 has harbored a heterozygous c.844C>T variant in the exon 8 of the NF1 gene, whilst child 2 has harbored a heterozygous c.1246C>T variant in the exon 11 of the NF1 gene. Both children were diagnosed with NF1 and have developed pronounced proteinuria, hypoalbuminemia, hypercholesterolemia and pitting edema at the ages of 3 and 10, respectively. Renal biopsy of child 2 has revealed minimal change nephropathy, and the diagnosis of nephrotic syndrome was established. Child 1 was treated with glucocorticoid, and child 2 was treated with glucocorticoid in combination with mycophenolate mofetil. The NS was relieved with no recurrence during 1 year's follow-up. CONCLUSION NF1 combined with NS is rare in the clinical settings. The prognosis of children with NF1 combined with minimal change nephropathy is relatively good. Detection of NF1 gene variant can facilitate early identification and diagnosis of NF1.
Child ; Humans ; Neurofibromatosis 1/genetics* ; Nephrotic Syndrome/genetics* ; Nephrosis, Lipoid ; Glucocorticoids ; Genetic Testing

Gastrointestinal stromal tumors(GISTs)in the stomach,duodenum,and rectum have low occurrence,and the coexistence GISTs in three parts with neurofibromatosis type Ⅰ(NF-Ⅰ)is even rare.This paper reports a case of GISTs with a family history of NF-Ⅰ.There were multiple nodular masses of different sizes on the patient's face,trunk,and limbs.The patient was admitted due to chest tightness for 5 days and black stools for 1 day.Enhanced CT examination of the abdomen suggested multiple space-occupying lesions in the upper abdomen with multiple small nodules under the abdominal wall,and neurofibromatosis and intestinal stromal tumor cannot be excluded.Finally,surgical pathology confirmed that the multiple tumors in the abdominal cavity were GISTs.The case was confirmed as wild-type GISTs by genetic testing,and the patient recovered well nearly one year after the operation.
Gastrointestinal Stromal Tumors/genetics* ; Humans ; Neurofibromatosis 1/genetics*

OBJECTIVE: To detect variants of NF1 gene among thirteen patients with neurofibromatosis type 1. METHODS: Genomic DNA was extracted from peripheral blood samples of the patients. High-throughput sequencing was employed to detect potential variants of the NF1 and NF2 genes. RESULTS: Thirteen pathogenic variants were identified among the patients, which included one NF1 deletion, three missense variants, three nonsense variants and six frameshifting variants. Among these, 10 variants have been associated with neurofibromatosis type 1. c.4180A>T (p.Asn1394Tyr), c.4217dupT (p.Leu1406fs) and c.1753dupT(p.Leu585Phefs*3) were unreported previously. Based on the guidelines of the American College of Medical Genetics and Genomics, c.4180A>T (p.Asn1394Tyr) was predicted to be likely pathogenic (PS2+PM1+PM2+PP2), while c.4217dupT (p.Leu1406fs) and c.1753dupT (p.Leu585Phefs*3) were predicted to be pathogenic (PVS1+PS2+PM2). CONCLUSION Variants of the NF1 gene probably underlay the disease among these children. Above findings have enriched the the spectrum of NF1 gene variants.
Child ; Genes, Neurofibromatosis 1 ; Genomics ; High-Throughput Nucleotide Sequencing ; Humans ; Mutation ; Neurofibromatosis 1/genetics*

OBJECTIVE: To explore the genetic basis for a patient with clinically suspected neurofibromatosis type I, alopecia areata and vitiligo. METHODS: Variant of the NF1 gene was detected by chip capture and high-throughput sequencing. Candidate variant was verified by Sanger sequencing of the family trio. RESULTS: The patient was found to harbor a novel missense c.1885G>A (p.Gly629Arg) variant of the NF1 gene, for which neither parent was carrier. The variant was not recorded in the public database. Based on the guidelines for genetic variation of the American College of Medical Genetics and Genomics, the c.1885G>A missense variant was predicted to be pathogenic (PS1+PS2+PM2+PP3+PP4). CONCLUSION The c.1885G>A missense variant probably underlay the disease in this child. Above finding has enriched the spectrum of the NF1 gene variants.
Alopecia Areata/genetics* ; Child ; Genomics ; Humans ; Mutation ; Neurofibromatosis 1/genetics* ; Vitiligo/genetics*

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with neurofibromatosis type I (NF1). METHODS: Target capture high-throughput sequencing and Sanger sequencing were carried out to detect the pathological variant in a NF1 patient and his parents. RESULTS: The proband and his similarly affected father have both harbored a novel nonsense variant of c.2511G>A (p.trp837x) in the NF1 gene. The same variant was not found in his mother and 200 healthy controls. CONCLUSION The heterozygous nonsense variant of c.2511G>A (p.trp837x) of the NF1 gene probably underlay the pathogenesis of NF1 in this pedigree.
China ; Heterozygote ; Humans ; Mutation ; Neurofibromatosis 1/genetics* ; Pedigree

Neurofibromatosis (NF) is a genetic disease in which the lungs are rarely involved. However, in NF cases with lung involvement, chest computed tomography may show bilateral basal reticulations, apical bullae, and cysts without bronchiectasis. Herein, we report a patient diagnosed with NF on the basis of the results of genetic testing who presented with early-onset wet cough and bronchiectasis. Considering the differential diagnosis of bronchiectasis combined with his early-onset wet cough, sinusitis, and sperm quality decline, we considered the possibility of primary ciliary dyskinesia (PCD). Further electron microscopy analysis of cilia and identification of homozygous mutations in the RSPH4A gene confirmed the diagnosis of PCD. Therefore, for patients with NF, when an image change exists in the lungs that does not correspond to NF, the possibility of other diagnoses, including PCD, must be considered.
Cilia ; Humans ; Kartagener Syndrome/genetics* ; Microscopy, Electron ; Mutation ; Neurofibromatosis 1/genetics*