Myelodysplastic syndrome (MDS) is a chronic hematologic disorder characterized by ineffective hematopoiesis, dysplasia of one or more cell lines with or without definite genetic changes. Its diagnosis requires a comprehensive analysis combining morphology, immunology, cytogenetics, and molecular biology findings. In recent years, the development of second-generation sequencing (NGS) has provided great assistance in exploring the molecular pathogenesis of hematological malignancies and guidance for clinical practice. Mutations of a series of gene involved in RNA splicing, DNA methylation, transcriptional regulation, signal transduction, chromatin modification and cohesin complex have been identified as important mechanisms for the development of MDS, among which some mutations have been found to play important roles in the diagnosis, treatment, and prognosis of MDS. This article has provided a comprehensive review the the common molecular genetic abnormalities involved in MDS.
Humans ; Myelodysplastic Syndromes/diagnosis* ; Mutation ; DNA Methylation ; RNA Splicing ; High-Throughput Nucleotide Sequencing

OBJECTIVE: To identify the nucleotide sequence of a novel HLA-DRB1*12:106 allele. METHODS: A blood donor who was joined into the database for platelet matching transfusion at the Blood Center of Zhejiang Province in 2023 was selected as the study subject. HLA genotyping was carried out through next-generation sequencing based on AllType NGS 11 locus, AllType FASTPlex NGS reagents, and Sanger sequencing method. The HLA genotype of the donor by Sanger sequencing and next generation sequencing were assigned by using uTYPE 7.3 and TypeStream Visual 3.0 software, respectively. This study was approved by Medical Ethics Committee of the Zhejiang Blood Center (Ethics No. Provincial Blood Center Ethics Review 2022 Research No. 001). RESULTS: A novel HLA-DRB1*12 allele has been identified, and the full coding sequence has been submitted to the GenBank database (No. OR101190), and the length of submitted sequence was 801 bp, which was officially named as HLA-DRB1*12:106 by the WHO Nomenclature Committee for Factors of the HLA System (submission No. HWS10066755). Compared with the sequence of the highest homology (HLA-DRB1*12:01:01:01 allele), a single nucleotide change was identified at position 344 T>G in the exon 2 of the HLA-DRB1*12:106, which has resulted in replacement of Valine by Glycine at residue 86. The HLA genotype of the proband was determined as HLA-A*02:01, 11:01;-B*13:02, 40:01;-C*01:02, 03:03;-DRB1*07:01, 12:106;-DRB3*01:01;-DRB4*01:03;-DQA1*02:01,04:01;-DQB1*02:02,04:02;-DPA1*01:03,01:03; -- DPB1*02:01:02G,04:01:01G. CONCLUSION A novel HLA-DRB1 allele has been identified in the Chinese population. The mutated amino acid, located in the peptide binding region of the β chain, may affect the binding characteristics of antigen peptides.
Humans ; HLA-DRB1 Chains/genetics* ; Alleles ; Base Sequence ; Genotype ; Male ; High-Throughput Nucleotide Sequencing ; Blood Donors

Next generation sequencing (NGS) technologies, including whole exome sequencing (WES) and whole genome sequencing (WGS), have greatly increased the diagnostic rates for genetic disorders. However, challenges still remain with the interpretation of variants of uncertain significance (VUS), variants in non-coding regions, and understanding of the effects of such variants on downstream genes. As a result, the diagnostic rates have typically ranged from 25% to 57%. RNA sequencing (RNA-seq) can complement DNA sequencing by revealing the functional consequences of genetic variants through the detection of aberrant gene expression, abnormal splicing events, allele-specific expression, and fusion gene expression. This has further increased the diagnostic rate of genetic disorders and enriched their therapeutic strategies. By broadening the scope of conventional genomic diagnostic methods, RNA-seq is poised to become a novel tool for the diagnosis of genetic disorders. This review has explored the methodologies and technical characteristics of RNA-seq by focusing on its recent advancement in clinical diagnosis, applications in undiagnosed genetic disorders, and the main challenges encountered.
Humans ; Genetic Diseases, Inborn/genetics* ; High-Throughput Nucleotide Sequencing/methods* ; Sequence Analysis, RNA/methods* ; Exome Sequencing/methods*

OBJECTIVE: To explore the molecular cytogenetic characteristics of three fetuses with psu idic(Y)(q11.22) using a combination of multiple methods. METHODS: A total of 11 000 pregnant women who underwent prenatal diagnosis at the Prenatal Diagnosis Center of Taizhou City from January 2019 to October 2024 were selected as the study subjects. Chromosome karyotype analysis (G-banding) and copy number variation analysis based on next-generation sequencing (NGS) were performed on the amniotic fluid/cord blood samples of the 11 000 fetuses. For cases suspected of Y chromosome abnormalities, C-banding and/or fluorescence in situ hybridization (FISH) and AZF microdeletion testing were additionally conducted. This study has been reviewed and approved by the Medical Ethics Committee of Taizhou Hospital, Zhejiang Province (Ethics No. KL20240860). RESULTS: Among the 11,000 prenatal samples undergoing concurrent karyotype and copy number variation analysis, two fetuses with 45,X/46,X,psu idic(Y)(q11.22) mosaicism and one fetus with 46,X,psu idic(Y)(q11.22) were detected. FISH detection indicated that approximately 66.7% of the cells in fetus 2 exhibited a dicentric Y chromosome, and the metaphase karyotype supported the presence of a pseudodicentric chromosome. AZF testing revealed complete deletion of the AZFb+AZFc regions in fetus 2 and fetus 3. CONCLUSION Conventional G-banding karyotype analysis for psu idic(Y)(q11.22) is prone to misdiagnosis or missed diagnosis. The combined application of chromosome karyotype analysis (G+C banding), copy number variation analysis, and FISH detection in clinical practice can accurately diagnose fetuses with psu idic(Y).
Humans ; Female ; Pregnancy ; Prenatal Diagnosis/methods* ; DNA Copy Number Variations/genetics* ; Adult ; Chromosomes, Human, Y/genetics* ; Karyotyping ; In Situ Hybridization, Fluorescence ; Cytogenetic Analysis/methods* ; Fetus ; High-Throughput Nucleotide Sequencing ; Male

OBJECTIVE: To provide preimplantation genetic testing (PGT) for a patient with Incontinentia pigmenti (IP) due to IKBKG gene variant but without family samples through construction of single nucleotide polymorphism (SNP)-based haplotype by Long-read sequencing (LRS) technology. METHODS: A female IP patient with a heterozygous IKBKG c.1167dup variant but without family genetic data who sought genetic counseling at Women and Children' Hospital of Ningbo University in November 2021 was selected as the study subject. The IKBKG gene has a highly homologous pseudogene IKBKGP1. Genomic DNA was extracted from peripheral blood samples from the couple, and LRS was used to obtain informative SNP loci flanking the variant locus, enabling the construction of SNP haplotype with a long segment spanning from the non-homologous region of IKBKG to the variant site. Trophoblast cells were biopsied from blastocysts fertilized through intracytoplasmic sperm injection, and next-generation sequencing (NGS) was used to determine the SNP information of the embryos. Linkage analysis with the parental SNP haplotypes was conducted to detect the carrier status of the embryos and exclude chromosomal aneuploidies. Sanger sequencing was carried out to validate the result. A euploid embryo without the pathogenic variant was selected for transfer. Prenatal diagnosis was carried out by amniocentesis at mid-trimester to verify the result of PGT tests, and follow-up was conducted after the baby was born. This study has been approved by the Ethics Committee of Women and Children's Hospital of Ningbo University (Ethics No. EC2023-094). RESULTS: A total of seven blastocysts were tested, and PGT results indicated that two embryos were euploid and did not carry the pathogenic variant. One euploid embryo was transferred, which resulted in a singleton pregnancy. Amniocentesis at 24 weeks of gestation confirmed that the status of fetal IKBKG gene, and its chromosomal status was consistent with the PGT results. A healthy male infant was born at 38+6 weeks of gestation. CONCLUSION For IP patients with de novo mutation or without family genetic samples, PGT with LRS can directly construct the SNP-based haplotype while avoiding interference from pseudogenes, providing an effective strategy for PGT.
Female ; Humans ; Male ; Pregnancy ; Genetic Testing/methods* ; Haplotypes/genetics* ; High-Throughput Nucleotide Sequencing/methods* ; I-kappa B Kinase/genetics* ; Incontinentia Pigmenti/diagnosis* ; Polymorphism, Single Nucleotide/genetics* ; Preimplantation Diagnosis/methods* ; Infant, Newborn

OBJECTIVE: To explore the genetic etiology of a Chinese pedigree with recurrent Joubert syndrome with negative results by whole-exome sequencing in the prior proband. METHODS: Chinese pedigree which opted elective abortion at the Women and Children's Hospital Affiliated to Chongqing Medical University in December 2024 was selected as the study subject. Whole-genome sequencing was carried out on fetal tissue after termination of pregnancy. Candidate variants were validated by Sanger sequencing and interpreted, while non-coding variant was analyzed using in silico prediction tools. RNA sequencing and cDNA sequencing were conducted on fetal brain tissue. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.2024YL045-02). RESULTS: Both the fetus and the affected child were found to harbor compound heterozygous variants of the CEP290 gene, namely c.7341dup (p.Leu2448fs*8) (pathogenic, maternally inherited) and c.1523-408G>A (likely pathogenic, paternally inherited). Both in silico analysis and fetal brain RNA sequencing confirmed aberrant RNA splicing caused by the intronic variant. CONCLUSION This case has highlighted the value of combining whole-genome sequencing with RNA functional validation. Above results not only enriched the spectrum of CEP290 gene mutations but also underscored its diagnostic value in resolving complex prenatal cases, providing critical clues for the prenatal diagnosis and recurrence risk assessment in genetic counseling.
Female ; Humans ; Pregnancy ; Abnormalities, Multiple/genetics* ; Antigens, Neoplasm/genetics* ; Cell Cycle Proteins/genetics* ; Cerebellum/abnormalities* ; Cytoskeletal Proteins/genetics* ; Eye Abnormalities/genetics* ; Introns/genetics* ; Kidney Diseases, Cystic/diagnosis* ; Pedigree ; Retina/abnormalities* ; Sequence Analysis, RNA/methods* ; Whole Genome Sequencing/methods* ; Child

OBJECTIVE: To explore the genetic basis for a woman with oocyte maturation disorder during assisted reproductive treatment (ART), and to verify the source of the variant and its impact on oocyte maturation through family verification. METHODS: A 35-year-old infertile woman presented at the Reproductive Medicine Center of Gansu Provincial Maternal and Child Health Care Hospital on 20 October 2023 for a 10-year history of infertility despite unprotected intercourse was selected as study subject. Peripheral venous blood sample was collected from the proband. Next-generation sequencing (NGS) was used to detect the potential variant. Candidate variants were validated within her family by Sanger sequencing, and their deleteriousness was assessed with comprehensive bioinformatic analyses to elucidate their origin and impact on oocyte maturation. According to the Standards and Guidelines for the Interpretation of Sequence Variants (hereinafter referred to as ACMG Guidelines) formulated by the American College of Medical Genetics and Genomics (ACMG), the pathogenicity of the candidate variant was rated. This study was approved by the Medical Ethics Committee of Gansu Provincial Maternal and Child Health Care Hospital (Ethics No.: 2023GSFYLS78). RESULTS: The proband underwent three controlled ovarian-stimulation cycles as part of assisted reproductive technology, yielding a total of 29 oocytes, among which only three were mature, whilst the remainders exhibited maturation arrest. Targeted sequencing of peripheral-blood DNA revealed a heterozygous c.728C>T (p.P243L) missense variant of the TUBB8 gene. While the same variant was detected in the proband's father. Based on the ACMG guidelines, the variant was classified to be likely pathogenic (PS4_Supporting+PM2_Supporting+PP2+PP3+PP4). CONCLUSION The heterozygous c.728C>T (p.P243L) missense variant of the TUBB8 gene probably underlay the oocyte maturation disorder in the proband, which may be either autosomal dominant or autosomal recessive. For probands with oocyte maturation disorders caused by the heterozygous c.728C>T variant of the TUBB8 gene, oocyte donation may be considered.
Humans ; Female ; Adult ; Mutation, Missense ; Oocytes/metabolism* ; Heterozygote ; Tubulin/genetics* ; Infertility, Female/genetics* ; High-Throughput Nucleotide Sequencing ; Pedigree

OBJECTIVE: To analyze the carrier rates and profiles of pathogenic and likely pathogenic variants for hearing loss-related genes MYO7A, PCDH15, and CDH23 among neonates in Nanjing city through targeted next-generation sequencing (NGS). METHODS: Heel-prick blood samples were collected from 30 043 newborns delivered at Nanjing Women and Children's Health Care Hospital between March 2022 and April 2024. Dried blood spots were prepared, and genomic DNA was extracted. Targeted NGS was applied to detect variants across the full coding regions of the MYO7A, PCDH15, and CDH23 genes. The carrier rates and profiles of pathogenic and likely pathogenic variants of the three genes were analyzed. This study was approved by the Medical Ethics Committee of Nanjing Maternal and Child Health Care Hospital (Ethics No.: 2021KY-071). RESULTS: The carrier rates of pathogenic and likely pathogenic variants (with ≥ 1 variant site) for the MYO7A, PCDH15, and CDH23 genes were 0.340%, 0.226%, and 0.156%, respectively. A total of 65, 49, and 30 variant types were detected in the MYO7A, PCDH15, and CDH23 genes, respectively. For MYO7A, single base variants were predominant, with the most common variant being c.5581C>T, followed by c.1343+1G>A, c.2837T>G, and c.5660C>T, with allelic frequencies of 0.013% (8/60 086), 0.007% (4/60 086), 0.007% (4/60 086), and 0.007% (4/60 086), respectively. PCDH15 variants were mainly deletions, with the most common variant site being c.4699_4715dupAGAGAAAAGATTCAGAG, followed by c.3441delA, c.440T>G, and c.4733_4736delTCAG, with allelic frequencies of 0.015% (9/60 086), 0.005% (3/60 086), 0.005% (3/60 086), and 0.005% (3/60 086), respectively. For CDH23, single base variants were predominant, with c.6604G>A being the most common, followed by c.6085C>T, c.6050+9G>A, and c.6253+1G>A, with allelic frequencies of 0.013% (8/60 086), 0.012% (7/60 086), 0.005% (3/60 086), and 0.005% (3/60 086). CONCLUSION This study analyzed the carrier rates and profiles of pathogenic and likely pathogenic variants of the MYO7A, PCDH15, and CDH23 genes, which can provide more evidence for the prevention and management of deafness in the region.
Humans ; Cadherins/genetics* ; High-Throughput Nucleotide Sequencing/methods* ; Infant, Newborn ; Female ; Myosin VIIa/genetics* ; Cadherin Related Proteins ; Male ; Hearing Loss/genetics* ; Myosins/genetics* ; Heterozygote

OBJECTIVE: The haplotypes of Killer cell immunoglobulin-like receptors (KIR) can be divided into centromeric and telomeric ones. As the terminal gene at the centromeric end, KIR3DP1 plays an important role in stabilizing the haplotype structure. This study aimed to analyze the distribution of KIR3DP1 gene haplotypes among Han Chinese population in Zhejiang in order provide a basis for further analyzing the role of KIR3DP1 in the KIR haplotypes. METHODS: A total of 166 unrelated blood donors from Zhejiang were collected (Blood donation period: March 2020 to August 2020), and genotyping was performed by next-generation sequencing based on exon capture. The copy number and allelic frequency of the KIR3DP1 gene and the distribution of centromeric haplotypes were statistically analyzed. This study was approved by the Medical Ethics Committee of Zhejiang Blood Center (Ethics No.: 2023-001). RESULTS: The KIR3DP1 gene was positive for all individuals but with different copy numbers. Among these, 4 cases (2.4%) had only 1 copy, 156 cases (94.0%) had 2 copies, and 6 cases (3.6%) had 3 copies. A total of 10 KIR3DP1 alleles were found in the population, which could be classified into the KIR3DP1*001-L type, KIR3DP1*003-L type, and KIR3DP1 full deletion type. The KIR3DP1*003 L type allele was linked to the Cen-A01 and Cen-B01 types, and the KIR3DP1*001*L type allele and the KIR3DP1 deletion type were only present in the Cen-B02 type haplotype. CONCLUSION This study has derived a high-resolution distribution map of the KIR3DP1 gene in the Han population from Zhejiang, and found that the KIR3DP1 alleles showed different linkage with the centromeric haplotypes, which has provided a basis for further studying the role of KIR3DP1 in genetic immunity.
Adult ; Female ; Humans ; Male ; Alleles ; China/ethnology* ; Gene Frequency ; Genotype ; Haplotypes/genetics* ; High-Throughput Nucleotide Sequencing/methods* ; East Asian People/genetics* ; Receptors, KIR/genetics*

OBJECTIVE: To explore the impact of age on the genetic variant spectrum and prognosis of patients with previously untreated Diffuse large B-cell lymphoma (DLBCL). METHODS: A retrospective analysis was conducted on the clinical data and follow-up information of 254 previously untreated DLBCL patients from 14 hospitals in the Jiangsu Cooperative Lymphoma Group (JCLG) enrolled from July 2018 and July 2023. Following extraction of DNA from tumor tissue samples, next-generation sequencing (NGS) technique was employed to analyze the genetic variant spectrum of the DLBCL patients, with an evaluation of the relationship between age and genetic variants as well as prognosis. This study was approved by the Medical Ethics Committee of the Affiliated Hospital of Nantong University (Ethics No.: 2023-K048-01). RESULTS: The median age of the 254 DLBCL patients was 62 years old, with 55% of patients aged 60 years or above. Clinical evaluation showed that younger (< 60 years) patients had higher complete response (CR) (70% vs. 59%), and objective response rate (ORR) (88% vs. 79%) than older patients, though the difference between the two groups was not statistically. Survival analysis indicated that both the five-year overall survival (OS) (82.7% vs. 71.7%, P = 0.006) and progression-free survival (PFS) (70.6% vs. 50.2%, P < 0.05) rates were significantly higher in younger patients. NGS showed that 99.6% of the patients harbored genetic variants, with PIM1, KMT2D, TP53, MYD88, and CD79B being the most common genes. Age significantly affected the variant frequency of certain genes, with MYC variants serving an adverse prognostic factor for OS in younger patients (P = 0.002), while TP53 (P = 0.024) and BCL2 (P = 0.002) variants significantly impacted OS in older patients. Prognostic analysis identified age ≥ 60 years (HR = 3.439, 95%CI: 1.318~9.874), presence of B symptoms (HR = 2.871, 95%CI = 1.133~7.307), and elevated lactate dehydrogenase (HR = 3.528, 95%CI = 1.231~10.66) as independent adverse prognostic factors. CONCLUSION Age, genetic variants, and clinical factors may significantly affect the prognosis of the DLBCL patients. Younger patients have better survival compared to older patients. Variants of the MYC, BCL2, and TP53 genes are closely associated with poor prognosis.
Humans ; Lymphoma, Large B-Cell, Diffuse/diagnosis* ; Middle Aged ; Female ; Male ; Retrospective Studies ; Aged ; Prognosis ; Adult ; Aged, 80 and over ; High-Throughput Nucleotide Sequencing ; Young Adult ; Adolescent ; Genetic Variation