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 etiology for a pregnant woman with a history of multiple adverse pregnancies and assess the phenotype-genotype correlation of 22q11.2 microduplication syndrome in her family. METHODS: Amniotic fluid sample was taken from a pregnant woman for whom non-invasive prenatal screening indicated chromosome 22 abnormalities in the fetus. Peripheral blood samples from the woman, her brother and parents were collected for high-throughput low-depth whole genome sequencing (CNV-seq). A pedigree traceability analysis of the results was conducted in conjunction with analysis of clinical manifestation. Relevant literature (from establishment to March 2025) was systematically searched. This study was approved by the Medical Ethics Committee of Mianyang Maternal and Child Health Care Hospital (Ethics No.: Lun Shen [2024]009). RESULTS: CNV-seq revealed that the fetus had harbored a 6.02 Mb duplication at 22q11.21q11.23. Karyotyping confirmed it as 46,X?dup(22)(q11.2). Pedigree verification demonstrated that the pregnant woman, her brother and mother had all carried the same duplication. Phenotypic analysis of the affected family members showed classic features of 22q11.2 microduplication syndrome, including hypernasal speech, low nasal bridge, congenital heart disease, and cognitive impairment. A total of 44 cases with full information (including three patients from this pedigree) were included in the analysis. The penetrance of 22q11.2 duplication was approximately 29.5% (13/44), and 52.3% (23/44) of the cases had inherited the variant from a phenotypically normal parent. CONCLUSION This study has identified the genetic basis for the woman's recurrent adverse pregnancies and phenotypic abnormalities in her family members. The scoliosis identified in her younger brother has not been previously reported, thereby may enrich the clinical phenotype of this syndrome. For fetuses identified with a 22q11.2 microduplication, detailed fetal imaging is recommended, and genetic counseling should be provided to the couples.
Humans ; Female ; Pregnancy ; Prenatal Diagnosis/methods* ; Chromosome Duplication/genetics* ; Male ; Pedigree ; DiGeorge Syndrome/diagnosis* ; Adult ; Chromosomes, Human, Pair 22/genetics* ; Abnormalities, Multiple

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with Hereditary spastic paraplegia type 3A (SPG3A) and the genotype-phenotype correlation. METHODS: A three-generation pedigree presented at Huantai Maternal and Child Health Care Hospital in March 2021 was selected as the study subject. Whole-exome sequencing (WES) and pedigree analysis was carried out. Candidate variant was validated by Sanger sequencing of the members from the pedigree. Haplotype analysis was used to trace the origin of the variant, and pathogenicity was rated based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: 2025-12). RESULTS: A c.1024C>T (p.Pro342Ser) variant of the ATL1 was identified in the four affected members, including the proband, but none of the three unaffected relatives. Haplotype analysis suggested that the variant was derived from the proband's mother and has co-segregated with the disease phenotype. Based on the guidelines of the ACMG, it was classified as likely pathogenic. CONCLUSION The ATL1 c.1024C>T (p.Pro342Ser) variant probably underlay the pathogenesis in this pedigree. Above finding has enriched the mutational spectrum of ATL1 and phenotypic spectrum of SPG3A in the Chinese population, and enabled genetic counseling for this pedigree.
Humans ; Pedigree ; Spastic Paraplegia, Hereditary/genetics* ; Male ; Female ; Asian People/genetics* ; Adult ; Haplotypes ; Membrane Proteins/genetics* ; Exome Sequencing ; GTP-Binding Proteins/genetics* ; Mutation ; Middle Aged ; China ; Genetic Association Studies ; East Asian People

OBJECTIVE: To explore the genotype-phenotype correlation in a Chinese family with structural brain abnormalities due to variant of the TUBB gene. METHODS: A family undergoing prenatal diagnosis at Beijing Obstetrics and Gynecology Hospital in October 2024 was selected as the study subject. Clinical data were collected. Amniotic fluid sample was subjected to chromosomal copy number variation sequencing (CNV-seq). Trio whole-exome sequencing (Trio-WES) was carried out on the amniotic fluid and parental blood samples, and candidate variant was verified by Sanger sequencing. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2023-KY-076-01). RESULTS: Both prenatal ultrasound and fetal MRI showed deviation of brain midline, unilateral lateral ventriculomegaly, and bilateral gyral asymmetry. Trio-WES revealed that the fetus has harbored a maternally derived heterozygous missense variant of the TUBB gene [NM_178014.4: c.155A>G (p.N52S)]. Sanger sequencing confirmed that the woman and a previously terminated fetus both harbored the same variant. Both the proband and two fetuses exhibited similar neuroimaging abnormalities including midline deviation and asymmetrical gyri. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic (PM2_Supporting+PS2_Moderate+PS3). CONCLUSION The heterozygous c.155A>G (p.N52S) variant was the TUBB gene probably underlay the pathogenesis of the structural brain abnormalities in this family. Above findings have expanded the phenotypic spectrum associated with the variant and facilitated the prenatal diagnosis for this family.
Humans ; Female ; Pregnancy ; Prenatal Diagnosis ; Tubulin/genetics* ; Adult ; Brain/diagnostic imaging* ; Male ; Pedigree ; DNA Copy Number Variations/genetics* ; Exome Sequencing ; Genetic Association Studies ; Magnetic Resonance Imaging

OBJECTIVE: To analyze the functional impact of a rare heterozygous variant of SOS1 gene (c.283G>A, p.E95K) identified in a fetus with cervical cystic hygroma and to explore its association with the disease phenotype. METHODS: A pedigree analysis was carried out to evaluate the co-segregation of the variant with the disease phenotype. Bioinformatic tools were employed to assess the conservation, protein structure and stability. Functional validation was conducted on HEK293T cells using fluorescence quantitative reverse transcription-PCR and Western blotting to measure the expression of SOS1 and phosphorylation levels of extracellular regulated protein kinases (ERK) and c-Jun N-terminal kinase. A literature review of previously reported disease-associated SOS1 variants was also carried out. This study has been approved by the Medical Ethics Committee of West China Second University Hospital, Sichuan University (Ethics No.: 201940). RESULTS: The variant was inherited from the husband of the woman with distinctive facial features and has co-segregated with the phenotype. Bioinformatics analysis indicated that the variant is located in a highly conserved region, and that p.E95K could disrupt key amino acid interactions and protein stability. Multiple bioinformatic predictions consistently suggested the pathogenicity of this variant. Functional assays demonstrated reduced SOS1 protein expression and decreased ERK phosphorylation. CONCLUSION This study has revealed the functional impact of the SOS1 c.283G>A (p.E95K) variant, suggesting that it may contribute to the developmental phenotypes through a haploinsufficiency mechanism.
Humans ; SOS1 Protein/chemistry* ; Female ; HEK293 Cells ; Male ; Pedigree ; Phenotype ; Adult

OBJECTIVE: To explore the serological and molecular genetic characteristics of a family with subtype B(A)06. METHODS: A neonatal hyperbilirubinemia patient who was treated at Henan Children's Hospital on June 15, 2023 due to "yellowing of the skin and gradual aggravation", and was found to have inconsistent ABO forward and reverse typing through blood type testing, was selected as the research subject. Six milliliters of peripheral blood were collected from the newborn and her family members (grandfather, grandmother, father, mother and aunt) respectively. ABO blood group identification was performed by the blood group serological method. Human genomic DNA was extracted using the nucleic acid extraction or purification reagent BT-01. ABO gene exons 2 to 7 were amplified by PCR. The PCR-specific products that were successfully amplified were sequenced by Sanger method. Taking ABO*A1.01 as the reference sequence, the ABO gene sequences of the newborn and her family members were analyzed to determine the ABO genotype. The procedures followed in this study were approved by the Ethics Committee of Henan Children's Hospital (Ethics No.: 2022-K-L036). RESULTS: The serological results of ABO blood group showed that the newborn, her grandfather, father and aunt were all incompatible with the forward and reverse typing. The blood group phenotype of the newborn was AwB or B(A), the blood group phenotype of the grandfather was A2B or B(A), the blood group phenotype of the father and aunt were A2B, and the blood group phenotype of the grandmother and mother were both O. The screening test results of hemolytic disease of the newborn showed that the free test detected IgG anti-A1 antibody, while the elution test, direct antiglobulin test and antibody screening results were all negative. The Sanger sequencing results showed that the newborn had variations of c.261delG, c.297A>G, c.526C>G, c.657C>T, c.703G>A, c.796C>A and c.930G>A. Her grandfather had variations of c.297A>G, C.526C>G, c.657C>T, c.703G>A, c.796C>A, c.803G>C and c.930G>A. Her grandmother had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.646T>A, c.681G>A, c.771C>T and c.829G>A. Her father and aunt had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.526C>G, c.646T>A, c.657C>T, c.681G>A, c.703G>A, c.771C>T, c.796C>A, c.829G>A and c.930G>A. Her mother had variations of c.106G>T, c.188G>A, c.189C>T, c.220C>T, c.261delG, c.297A>G, c.646T>A, c.681G>A, c.771C>T, and c.829G>A.The genotype of the newborn was ABO*BA.06/ABO*O.01.01, her grandfather was ABO*BA.06/ABO*B.01, her grandmother was ABO*O.01.02/ABO*O.01.02, her father and aunt were ABO*BA.06/ABO*O.01.02, and her mother was ABO*O.01.01/ABO*O.01.02. The ABO*BA.06 allele of the newborn, grandfather, father and aunt was caused by the c.803C>G variation in exon 7 based on the ABO*B.01 allele. The ABO*BA.06 allele can be stably inherited in this family. CONCLUSION The blood type of neonatal patients with B(A)06 subtype can be accurately determined by gene sequencing technology. If the forward typing is ≤ 3+ agglutination intensity in newborn ABO blood group identification, the reason should be carefully analyzed, and the molecular biology technology and family gene sequencing results should be used to jointly determine if necessary.
Humans ; ABO Blood-Group System/genetics* ; Female ; Pedigree ; Male ; Infant, Newborn ; Asian People/genetics* ; Genotype ; China ; Blood Grouping and Crossmatching ; Hyperbilirubinemia, Neonatal/blood* ; East Asian People

OBJECTIVE: To explore the genetic etiology of 46 Chinese pedigrees affected with Hereditary multiple exostoses (HME) and provide genetic counseling and reproductive intervention. METHODS: Whole-exome sequencing and Sanger sequencing were carried out on 87 patients from the 46 pedigrees to analyze the variants of EXT1 and EXT2 genes. Pathogenicity of the variants was assessed based on the guidelines from the American College of Medical Genetics and Genomics and Association for Molecular Pathology (ACMG/AMP). Prenatal diagnosis and preimplantation genetic testing (PGT) were provided for couples with identified pathogenic mutations. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: LL-SC-SG-2014-010). RESULTS: In total 17 and 22 pathogenic variants were respectively identified in the EXT1 and EXT2 genes, among which 5 EXT1 and 12 EXT2 variants were unreported previously. Three patients with no family history were found to harbor de novo variants of the EXT1 gene. Twenty nine couples had opted for PGT or underwent prenatal diagnosis following natural conception, and 17 healthy babies were born. CONCLUSION This study has clarified the genetic etiology of 45 HME pedigrees and identified 17 novel variants, which has enriched the mutational spectrum of the EXT1 and EXT2 genes. Reproductive intervention through PGT and prenatal diagnosis have prevented the recurrence of HME in these families.
Humans ; Female ; Male ; Pedigree ; Exostoses, Multiple Hereditary/diagnosis* ; N-Acetylglucosaminyltransferases/genetics* ; Adult ; Exostosin 1 ; Asian People/genetics* ; Genetic Testing ; Exostosin 2 ; Mutation ; China ; Prenatal Diagnosis ; Pregnancy ; Genetic Counseling ; Preimplantation Diagnosis ; Exome Sequencing ; East Asian People

Primary ciliary dyskinesia (PCD) is a clinically rare, genetically and phenotypically heterogeneous condition characterized by chronic respiratory tract infections, male infertility, tympanitis, and laterality abnormalities. PCD is typically resulted from variants in genes encoding assembly or structural proteins that are indispensable for the movement of motile cilia. Here, we identified a novel nonsense mutation, c.466G>T, in cilia- and flagella-associated protein 300 ( CFAP300 ) resulting in a stop codon (p.Glu156*) through whole-exome sequencing (WES). The proband had a PCD phenotype with laterality defects and immotile sperm flagella displaying a combined loss of the inner dynein arm (IDA) and outer dynein arm (ODA). Bioinformatic programs predicted that the mutation is deleterious. Successful pregnancy was achieved through intracytoplasmic sperm injection (ICSI). Our results expand the spectrum of CFAP300 variants in PCD and provide reproductive guidance for infertile couples suffering from PCD caused by them.
Adult ; Female ; Humans ; Male ; Pregnancy ; China ; Ciliary Motility Disorders/genetics* ; Codon, Nonsense ; East Asian People/genetics* ; Exome Sequencing ; Homozygote ; Infertility, Male/genetics* ; Kartagener Syndrome/genetics* ; Pedigree ; Sperm Injections, Intracytoplasmic ; Cytoskeletal Proteins/genetics*

Multiple morphological abnormalities of the flagella (MMAF) represent a severe form of sperm defects leading to asthenozoospermia and male infertility. In this study, we identified a novel homozygous splicing mutation (c.871-4 ACA>A) in the adenylate kinase 7 (AK7) gene by whole-exome sequencing in infertile individuals. Spermatozoa from affected individuals exhibited typical MMAF characteristics, including coiled, bent, short, absent, and irregular flagella. Transmission electron microscopy analysis showed disorganized axonemal structure and abnormal mitochondrial sheets in sperm flagella. Immunofluorescence staining confirmed the absence of AK7 protein from the patients' spermatozoa, validating the pathogenic nature of the mutation. This study provides direct evidence linking the AK7 gene to MMAF-associated asthenozoospermia in humans, expanding the mutational spectrum of AK7 and enhancing our understanding of the genetic basis of male infertility.
Humans ; Male ; Sperm Tail/ultrastructure* ; Homozygote ; Consanguinity ; Asthenozoospermia/pathology* ; Infertility, Male/genetics* ; Mutation ; Pakistan ; Adenylate Kinase/genetics* ; Adult ; Pedigree ; RNA Splicing ; Exome Sequencing ; Spermatozoa

Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella (MMAF). Distinct projections encircling the central microtubules of the spermatozoal axoneme play pivotal roles in flagellar bending and spermatozoal movement. Mammalian sperm-associated antigen 17 ( SPAG17 ) encodes a conserved axonemal protein of cilia and flagella, forming part of the C1a projection of the central apparatus, with functions related to ciliary/flagellar motility, skeletal growth, and male fertility. This study investigated two novel homozygous SPAG17 mutations (M1: NM_206996.2, c.829+1G>T, p.Asp212_Glu276del; and M2: c.2120del, p.Leu707*) identified in four infertile patients from two consanguineous Pakistani families. These patients displayed the MMAF phenotype confirmed by Papanicolaou staining and scanning electron microscopy assays of spermatozoa. Quantitative real-time polymerase chain reaction (PCR) of patients' spermatozoa also revealed a significant decrease in SPAG17 mRNA expression, and immunofluorescence staining showed the absence of SPAG17 protein signals along the flagella. However, no apparent ciliary-related symptoms or skeletal malformations were observed in the chest X-rays of any of the patients. Transmission electron microscopy of axoneme cross-sections from the patients showed incomplete C1a projection and a higher frequency of missing microtubule doublets 1 and 9 compared with those from fertile controls. Immunofluorescence staining and Western blot analyses of spermatogenesis-associated protein 17 (SPATA17), a component of the C1a projection, and sperm-associated antigen 6 (SPAG6), a marker of the spring layer, revealed disrupted expression of both proteins in the patients' spermatozoa. Altogether, these findings demonstrated that SPAG17 maintains the integrity of spermatozoal flagellar axoneme, expanding the phenotypic spectrum of SPAG17 mutations in humans.
Humans ; Male ; Infertility, Male/pathology* ; Sperm Tail/ultrastructure* ; Homozygote ; Microtubule-Associated Proteins/genetics* ; Axoneme/genetics* ; Spermatozoa/ultrastructure* ; Adult ; Mutation ; Sperm Motility/genetics* ; Pedigree ; Microtubules ; Microtubule Proteins/genetics*