OBJECTIVE: To delineate the clinical and genetic features of a Chinese girl harboring a rare de novo variant of SYNGAP1 associated with Mental retardation, autosomal dominant 5 (MRD5), and to conduct a comprehensive genotype-phenotype correlation analysis within the Chinese population through an extensive literature review. METHODS: A 5-year-old girl presenting with seizures without an obvious cause was enrolled in September 2020. Genomic DNA was extracted from the patient and her parents. Whole exome sequencing (WES) was performed on the proband to identify suspected pathogenic variants based on her clinical phenotype. Sanger sequencing was used for validation, followed by bioinformatic analysis of the variant. Additionally, data from 54 previously reported Chinese cases with SYNGAP1 variants were integrated to summarize the distribution of variant types and clinical characteristics. Ethical approval was obtained from the Ethics Committee of Kunming Children's Hospital (Ethics No.: 2021-03-055-K01). RESULTS: WES identified a heterozygous nonsense variant, SYNGAP1 c.725G>A (p.Trp242*), in the proband. Sanger sequencing confirmed it was a de novo variant. According to the ACMG guidelines, this variant was classified as pathogenic (PVS1+PS2). Based on the clinical manifestations, the patient was diagnosed with MRD5. Bioinformatic analysis suggested that this variant introduces a premature stop codon at tryptophan 242, disrupting the PH domain and leading to the loss of the C2, Ras-GAP, and C-terminal domains. The pooled analysis of Chinese cases revealed that nonsense (38.2%) and frameshift (36.4%) variants were the predominant types. Intellectual disability/developmental delay was present in 100.0% of patients, epilepsy in 83.6%, and autism spectrum disorder in 41.3%. The incidence of epilepsy differed significantly among variant types (P = 0.045). Exons 8 and 15 were identified as mutation hotspots. CONCLUSION This study has identified a SYNGAP1 c.725G>A variant in the Chinese population and confirmed it as a potential cause of MRD5, which expanded the mutational spectrum of this disorder.
Humans ; Female ; Child, Preschool ; Intellectual Disability/genetics* ; ras GTPase-Activating Proteins/genetics* ; Phenotype ; Exome Sequencing ; Genetic Association Studies

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 elucidate the epidemiological characteristics and genetic variant profile of Short-chain acyl-CoA dehydrogenase deficiency (SCADD) among newborns from Hainan Province and evaluate its significance within the local neonatal disease screening panel. METHODS: A total of 84 184 newborns born in Hainan Province from February to December 2024 were included. Tandem mass spectrometry (MS/MS) was employed to detect butyrylcarnitine (C4) and propionylcarnitine (C3) levels in dried blood spots. Screening thresholds were set at C4 > 0.43 μ mol/L and C4/C3 ratio > 0.28. Suspected cases underwent confirmatory testing via urinary ethylmalonic acid analysis by gas chromatography-mass spectrometry and whole-exome sequencing for ACADS gene variants. This study was approved by the Medial Ethics Committee of the hospital (Ethics No.: HNWCMC-2024-55). RESULTS: Six SCADD cases (male-to-female ratio = 1:1) were diagnosed, with all carrying compound heterozygous variants at two loci, yielding a prevalence of 7.13 per 100,000 live births. Four known ACADS gene variants were identified, with both c.322G>A and c.625G>A detected at a frequency of 41.7%. Regular follow-up (as of January 2026) revealed that all diagnosed cases have remained asymptomatic with normal growth and development. CONCLUSION The prevalence of SCADD among newborns in Hainan Province is relatively high, with c.322G>A and c.625G>A as the hotspot variants in the region. Given the absence of clinical phenotypes in all screen-detected cases during long-term follow-up, it is recommended to remove this condition from the routine neonatal screening program for this region to reduce unnecessary anxiety and medical cost.
Humans ; Infant, Newborn ; Neonatal Screening/methods* ; Female ; Male ; Lipid Metabolism, Inborn Errors/epidemiology* ; Acyl-CoA Dehydrogenase/genetics* ; China/epidemiology* ; Follow-Up Studies

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

OBJECTIVE: To summarize the clinical and genetic characteristics of children with Silver-Russell syndrome (SRS) and improve the recognition of this disease. METHODS: A retrospective analysis was conducted on the clinical manifestations and genetic testing results of 29 children with SRS diagnosed at the Children's Hospital Affiliated to Zhengzhou University between March 2016 and June 2025. RESULTS: The 29 children had included 18 boys and 11 girls, with the age ranging from 2 months to 16 years. Their primary clinical manifestations included postnatal growth retardation (100%), small for gestational age (SGA) (100%), characteristic facial features (90%), limb asymmetry (83%), feeding difficulties (76%), ulnar deviation of the fifth finger (69%), body mass index (BMI) of < -2 SD (62%), and abnormal bone age (55%), including 15 cases with delayed bone age for an average of 1.5 years and 1 case with advanced bone age for 2.5 years. Additional manifestations included abnormal sexual development in 11 cases (38%), dental malocclusion in 11 cases (38%), allergic diseases in 10 cases (34%), cardiac diseases in 9 cases (31%), skeletal abnormalities in 7 cases (24%), renal hypoplasia in 5 cases (17%), and abnormal cranial MRI findings in 5 cases (17%). Twenty children were treated with recombinant human growth hormone (rhGH) at a dose of 0.1 ~ 0.15 U/(kg.d). Among them, 7 cases achieved annual height increase of ≥ 10 cm, 11 cases achieved annual height increase of ≥ 5 ~ 9 cm, and 2 cases achieved annual height increase < 5 cm. Twenty three children exhibited hypomethylation of imprinted genes in the chromosome region of 11p15, 4 presented maternal uniparental disomy of chromosome 7 [UPD(7)mat], and 2 had harbored nonsense variants of the HMGA2 gene. CONCLUSION SRS patients may present with diverse clinical manifestations including postnatal growth retardation, SGA, characteristic facial features, limb asymmetry, feeding difficulties, and ulnar deviation of the fifth finger. Most patients may exhibit abnormal methylation in the 11p15 region. rhGH therapy can improve the height of these patients.
Humans ; Silver-Russell Syndrome/diagnosis* ; Male ; Female ; Child ; Child, Preschool ; Infant ; Adolescent ; Retrospective Studies

OBJECTIVE: To analyze the clinical characteristics of patients with 11q23 rearrangement acute lymphoblastic leukemia (ALL) with non-KMT2A::AFF1 fusion genes. METHODS: The clinical data of 10 patients with KMT2A fusion gene positive and partner gene non-AFF1 ALL admitted to Henan Cancer Hospital from December 2016 to December 2024 were retrospectively summarized. The immunophenotype, molecular genetic characteristics, clinical manifestations and disease prognosis of these patients were analyzed. This research has been approved by the Medical Ethics Committee of Henan Cancer Hospital (Ethics No.: 2019342). RESULTS: Among the 10 patients, the fusion genes were KMT2A::MLLT1 in 7 cases, KMT2A::MLLT4, KMT2A::MLLT3 and KMT2A::MLLT10 in 1 case each. The European Group for the Immunological Classification of Leukemias (EGIL) classification included 6 cases of T-ALL, 2 cases of pro-B-ALL, 1 case of Common-B-ALL and 1 case of pre-B-ALL. 4 cases of B-ALL all expressed CD19, cCD79a, CD38 and HLA-DR, and some expressed CD34 and CD22, without expression or weak expression of CD10, without expression of CD20. One case was accompanied by myeloid marker CD15 expression. 6 cases of T-ALL all expressed CD34, CD7, most expressed CD38, and some expressed CD3, CD5, CD2, CD4 and CD8, and 1 case expressed CD4 and CD8 together. Chromosomal abnormalities were detected in 3 cases, 5 cases were positive for WT1 fusion gene, and 6 cases had gene alterations. 9 patients achieved the first complete remission (CR1) during chemotherapy, and 1 patient relapsed within 6 months after CR1. At the last follow up, 1 patient (the fusion gene was KMT2A::MLLT4) remained unrelieved. There were 2 cases of KMT2A rearrangement (KMT2A-r) persistent positive (+/+) and 8 cases of KMT2A-r negative (+/-). The overall survival (OS) rate and leukemia-free survival (LFS) rate of patients with KMT2A-r persistent positive were significantly lower than those of patients with negative change, and the differences were statistically significant (P values were all < 0.05). Among the 3 patients who received chemotherapy+allogeneic hematopoietic stem cell transplantation (allo-HSCT), no relapse was observed until the follow up day. The OS rate and LFS rate of patients with KMT2A::MLLT1 and chemotherapy+allo-HSCT were higher than those of non-KMT2A::MLLT1 and single chemotherapy patients, and the differences were not statistically significant (P values were all ≥ 0.05). There was no significant difference in OS rate and LFS rate between T-ALL and B-ALL patients (P values were all ≥ 0.05). The median LFS time of the 10 patients was 32 (0 ~ 100) months, and the median OS time was 36 (1 ~ 101) months. CONCLUSION The 11q23 rearrangement ALL with non-KMT2A::AFF1 transcript is mainly KMT2A::MLLT1, T-ALL is more common, and the rate of chromosomal karyotype detection is relatively low. Persistent positive KMT2A-r is unfavorable for patient survival, and allo-HSCT during the CR1 period may improve patient survival.
Humans ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics* ; Female ; Male ; Myeloid-Lymphoid Leukemia Protein/genetics* ; Histone-Lysine N-Methyltransferase/genetics* ; Adult ; Adolescent ; Chromosomes, Human, Pair 11/genetics* ; Child ; Transcriptional Elongation Factors/genetics* ; Gene Rearrangement ; Oncogene Proteins, Fusion/genetics* ; Retrospective Studies ; Young Adult ; Middle Aged ; Prognosis ; Child, Preschool ; DNA-Binding Proteins/genetics*

OBJECTIVE: To investigate the clinical characteristics, steroid hormone profiles, and genetic variants in two female patients with Non-classic adrenal hyperplasia (NCAH). METHODS: Clinical data and samples were collected from two patients who had visited Huaian Maternal and Child Health Care Hospital Affiliated to Medical College of Yangzhou University on September 27, 2022 and June 25, 2023, respectively, with an initial diagnosis of Polycystic ovary syndrome (PCOS) and suspected NCAH. Seven steroid hormones in dried blood spots were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Single base variants and repeat/deletions in the CYP21A2 gene were analyzed by using a classic congenital adrenal hyperplasia (CAH) gene assay, and 10 related genes were analyzed by third-generation sequencing (TGS) should the variants be unclear. This study has been approved by the Medical Ethics Committee of the hospital (Ethics No.: 2025003). RESULTS: Patient 1 was a 14-year-old girl, and patient 2 was a 23-year-old woman with insulin resistance. Both patients had hirsutism, acne, bilateral polycystic ovarian morphology, in addition with significantly elevated serum testosterone by chemiluminescence. The steroid hormone profiles of both patients suggested a significant increase in 17-hydroxyproesterone, normal cortisol and 11-deoxycortisol. Patient 2 additionally showed a significant rise in 21-deoxycortisol. The presentation of both patients was indicative of NCAH, which was also evidenced by their respective medical histories. Sanger sequencing of long fragment PCR amplification combined with multiplex ligation-dependent probe amplification (MLPA) revealed that patient 1 harbored a mild c.92C>T (p.P31L) variant and a severe variant with a large segmental deletion in CYP21A2. Patient 2 was finally confirmed by TGS to carry mild CYP21A2 variants in the 5' untranslated region (5' UTR) promotor region (c.-126C>T, c.-113G>A, c.-110T>C) and a severe c.293-13C/A>G variant. The promotor region variants had resulted in decompression of the long fragment P1X/P2 amplification, leading to homozygous result of Sanger sequencing for c.293-13C/A>G, which in turn halved the amplification signal for the wt-113 SNP probe. In addition, the wtI2G-A probe was enhanced by interference in the MLPA assay. CONCLUSION This study demonstrated that NCAH should be excluded when PCOS is accompanied by a significant increase in serum testosterone, that mass spectrometry of steroid hormone profiles containing 17-hydroxyprogesterone is useful for the detection of NCAH, and that TGS is advantageous in confirming the diagnosis of NCAH when compared with conventional genetic testing methods.
Humans ; Female ; Adrenal Hyperplasia, Congenital/blood* ; Adolescent ; Steroid 21-Hydroxylase/genetics* ; Young Adult ; Genetic Variation ; Adult

OBJECTIVE: To explore the efficacy of a Thalassemia risk assessment software for the screening of thalassemia mutation carriers and distribution of thalassemia genotypes detected by screening. METHODS: A total of 6 040 individuals were evaluated at Leshan Maternal and Child Health Care Hospital between 2022 and 2024 using the commonly used clinical thalassemia risk assessment method and the thalassemia screening software, respectively, and the performance indicators of the two methods were compared and analyzed against the result of thalassemia gene testing. This study was approved by the Ethics Committee of our hospital (Ethics No.: LfyLL[2022]005). RESULTS: The high-risk rate by the thalassemia screening software was 11.19%, with a sensitivity of 95.12%, specificity of 93.28%, positive predictive value of 43.20%, negative predictive value of 99.72%, and the area under the ROC curve (AUC) was 0.942. The thalassemia gene detection rate of the high-risk samples screened was 4.83%. The high-risk screening rate of the conventional method was 2.50%, with a sensitivity of 51.22%, specificity of 93.28%, positive predictive value of 80.79%, negative predictive value of 97.40%, and the AUC was 0.754. The thalassemia gene detection rate of the high-risk samples was 2.02%. CONCLUSION The software can effectively detect thalassemia carriers and significantly reduce the missed detection compared with conventional method, thereby significantly improve the efficacy of screening.
Humans ; Thalassemia/diagnosis* ; Software ; Female ; Genetic Testing/methods* ; Male ; Mutation ; Adult ; Genotype ; ROC Curve ; Risk Assessment

OBJECTIVE: To investigate the genetic etiology of a fetus diagnosed with Mandibulofacial dysostosis with microcephaly (MFDM). METHODS: A fetus that underwent prenatal diagnosis at Beijing Obstetrics and Gynecology Hospital, Capital Medical University, on May 19, 2025 was selected for analysis. Results of fetal ultrasound findings, chromosomal karyotyping, copy number variation sequencing (CNV-seq), and whole-exome sequencing (WES) were collected. Sanger sequencing was performed for familial validation of the pathogenic variant. The Human Protein Atlas (HPA), STRING, and Simple ClinVar databases were queried to characterize the biological features of the candidate gene. Three-dimensional structures of the wild-type and variant proteins were modeled and analyzed, and the evolutionary conservation of the affected amino acid was assessed using UGENE. Prenatal phenotypes associated with EFTUD2 variants were summarized through a review of the literature. This study was approved by the Ethics Committee of Beijing Obstetrics and Gynecology Hospital, Capital Medical University (Ethics No.: 2025-KY-029-01). RESULTS: At 23⁺² weeks of gestation, ultrasound examination revealed bilateral microtia with low-set ears, mild micrognathia with a reduced mandibular-facial angle, a single umbilical artery, a slightly narrow aortic diameter, and trivial mitral regurgitation. Amniotic fluid karyotyping and CNV-seq showed no abnormalities. WES identified a de novo, previously unreported EFTUD2 variant, c.698dupA (p.V235Gfs*27), in the fetus. This frameshift variant is predicted to alter the structural integrity of the EFTUD2 protein. Literature review indicated that micrognathia and microtia or low-set ears are the most common sonographic features in fetuses with EFTUD2 variants, while secondary findings may include abnormal stomach bubble, cleft palate, single umbilical artery, gastrointestinal atresia, polyhydramnios, and reduced aortic diameter. CONCLUSION The EFTUD2: c.698dupA (p.V235Gfs*27) variant is likely the genetic cause underlying MFDM in this fetus.
Humans ; Mandibulofacial Dysostosis/diagnostic imaging* ; Microcephaly/diagnostic imaging* ; Female ; Pregnancy ; Ribonucleoprotein, U5 Small Nuclear/chemistry* ; Peptide Elongation Factors/chemistry* ; Fetus ; DNA Copy Number Variations/genetics* ; Adult ; Ultrasonography, Prenatal

OBJECTIVE: To investigate the clinical manifestations and genetic etiology of a fetus with Neurodevelopmental disorders with deformed facial features and distal skeletal abnormalities (NEDDFSA). METHODS: Clinical data of a NEDDFSA fetus diagnosed at the Affiliated Women and Children's Hospital Affiliated to Ningbo University in March 2025 was selected as the study subject. Whole-exome sequencing (WES) was carried out on the amniotic fluid and parental peripheral blood samples, and candidate variants was verified by Sanger sequencing. The pathogenicity of candidate variant was rated based on 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.: EC2023-094). RESULTS: At 30 weeks of gestation, the fetus was found to have microcephaly, short femur and intrauterine growth restriction. WES revealed that the fetus harbored a de novo heterozygous frameshift variant c.2633dup (p.Gly879ArgfsTer22) of the ZMIZ1 gene, which was rated as pathogenic (PM2_Supporting+PS2_Supporting+PVS1). Combined with 25 cases from the literature, the main manifestations of patients have included intellectual disability, growth retardation and cranio-limb skeletal dysplasia, albeit without clear genotype-phenotype correlation. CONCLUSION The de novo variant c.2633dup (p.Gly879ArgfsTer22) of the ZMIZ1 gene probably underlay the NEDDFSA in this fetus. Genetic testing has enabled accurate prenatal diagnosis and provided evidence for genetic counseling and reproductive guidance of this family.
Humans ; Female ; Pregnancy ; Neurodevelopmental Disorders/genetics* ; Transcription Factors/genetics* ; Fetus/abnormalities* ; Exome Sequencing ; Prenatal Diagnosis