1.A case of complex structural variants in the Xq28 region diagnosed by whole genome sequencing.
Yulai YANG ; Chuang LI ; Ming GAO ; Yuan LYU
Chinese Journal of Medical Genetics 2025;42(3):355-359
OBJECTIVE:
To re-analyze a likely pathogenic variant in the Xq28 region identified by copy number variation sequencing (CNV-seq) through whole genome sequencing (WGS).
METHODS:
A fetus found to harbor a duplication in the Xq28 region by CNV-seq at Shengjing Hospital Affiliated to China Medical University in May 2023 was selected as the study subject. WGS was carried out for the fetus and its parents. Bioinformatic software was used to analyze the chromosomal structure and CNVs. Quantitative PCR (qPCR) was applied to determine the expression level of the MECP2 gene. This study has been approved by the Ethics Committee of Shengjing Hospital (Ethic No. 2013PS33K).
RESULTS:
A duplication (ChrX:153302641_153503563) and four breakpoints were identified on the X chromosome of the fetus' father. Bioinformatic analysis revealed that the duplicated region has involved exons 1 to 3 and part of the 5'-UTR of the MECP2 gene, which was inserted into the Xp11 region. Additionally, an inversion was detected in the Xp11 region adjacent to the duplicated segment. RT-PCR results showed normal level of MECP2 mRNA expression. The Xq28 duplication has not encompassed the entire MECP2 gene, nor disrupted its structure or altered its expression.
CONCLUSION
WGS has enabled more precise diagnosis of chromosomal structural variants and provided guidance for accurate genetic counseling for the affected families.
Humans
;
Female
;
Chromosomes, Human, X/genetics*
;
DNA Copy Number Variations/genetics*
;
Whole Genome Sequencing/methods*
;
Methyl-CpG-Binding Protein 2/genetics*
;
Pregnancy
;
Male
;
Adult
2.Identification of a novel deep intronic variant associated with Joubert syndrome through combined whole-genome sequencing and RNA sequencing.
Fang LIU ; Yan JIANG ; Xin GUI ; Yangxue XIAO ; Xiaohang ZHANG ; Xuemei ZHANG ; Yali GAO
Chinese Journal of Medical Genetics 2025;42(5):597-602
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
3.Analysis of a child with Congenital leukemia and mosaicism trisomy 21 syndrome without GATA1 gene mutation.
Liya ZHANG ; Yu LIU ; Yu DING ; Lulu YAN ; Fei LI ; Qingqing JIE ; Shuni SUN ; Lili CHEN ; Xiamin JIN
Chinese Journal of Medical Genetics 2025;42(6):751-755
OBJECTIVE:
To explore the genetic characteristics and pathogenesis for a child with mosaicism trisomy 21 and Congenital leukemia (CL).
METHODS:
A child who was admitted to Ningbo Women and Children's Hospital in March 2023 was selected as the study subject. A retrospective analysis was carried out on the clinical data, laboratory test results, immunophenotyping, and genetic characteristics of the child. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: EC2024-063).
RESULTS:
Whole genome sequencing (WGS) revealed that the child has mosaicism trisomy of chromosome 21, with a ratio of approximately 74%. In addition, copy number variations involving multiple OMIM genes that could explain his clinical phenotype were detected and rated as pathogenic based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). No pathogenic variant was detected with the GATA1 gene. Blood immune typing of the child conformed to the immunophenotype of acute myeloid leukemia.
CONCLUSION
For children with trisomy 21, even in the absence of GATA1 gene variants, the occurrence of CL should be monitored, and early diagnosis and treatment are of great significance for improving the prognosis.
Child, Preschool
;
Humans
;
DNA Copy Number Variations/genetics*
;
Down Syndrome/genetics*
;
GATA1 Transcription Factor/genetics*
;
Leukemia/congenital*
;
Mosaicism
;
Mutation
;
Retrospective Studies
;
Whole Genome Sequencing
4.Analysis of the chloroplast genome of Incarvillea younghusbandii Sprague.
Yaying ZHANG ; Wanyao JIAO ; Wenrui JIAO ; Tianle QIAO ; Zhiyang SU ; Shuo FENG
Chinese Journal of Biotechnology 2023;39(7):2954-2964
Incarvillea younghusbandii Sprague is a traditional tonic herb. The roots are used as herbal medicine for nourishing and strengthening, as well as treating postpartum milk deficiency and weakness. In this study, the chloroplast genome of I. younghusbandii was sequenced and assembled by the high-throughput sequencing technology. The sequence characteristics, sequence repeats, codon usage bias, phylogenetic relationships and estimated divergence time of I. younghusbandii were analyzed. The 159 323 bp sequence contained a large single copy (80 197 bp), a small single copy (9 030 bp) and two inverted repeat sequences (35 048 bp). It contained 120 genes, including 77 protein coding genes, 8 ribosomal RNA genes and 35 transfer RNA genes. AAA was the most frequent codon in the chloroplast coding sequence of I. younghusbandii. A total of 42 simple sequence repeats were identified in the chloroplast genome. Phylogenetic analysis revealed I. younghusbandii was mostly like its taxonomically close relative Incarvillea compacta. The divergence between I. younghusbandii and I. compacta was dated to 4.66 million years ago. This study was significant for the scientific conservation and development of resources related to I. compacta. It also provides a basic genetic resource for the subsequent species identification of the genus Incarvillea, and the population genetic diversity study of Bignoniaceae.
Phylogeny
;
Molecular Sequence Annotation
;
Genome, Chloroplast
;
Sequence Analysis, DNA
;
Whole Genome Sequencing
5.Complete chloroplast genome sequencing and phylogeny of wild Atractylodes lancea from Yuexi, Anhui province.
Jian-Peng HU ; Lu JIANG ; Rui XU ; Jun-Xian WU ; Feng-Ya GUAN ; Jin-Chen YAO ; Jun-Ling LIU ; Ya-Zhong ZHANG ; Liang-Ping ZHA
China Journal of Chinese Materia Medica 2023;48(1):52-59
This study investigated the choroplast genome sequence of wild Atractylodes lancea from Yuexi in Anhui province by high-throughput sequencing, followed by characterization of the genome structure, which laid a foundation for the species identification, analysis of genetic diversity, and resource conservation of A. lancea. To be specific, the total genomic DNA was extracted from the leaves of A. lancea with the improved CTAB method. The chloroplast genome of A. lancea was sequenced by the high-throughput sequencing technology, followed by assembling by metaSPAdes and annotation by CPGAVAS2. Bioiformatics methods were employed for the analysis of simple sequence repeats(SSRs), inverted repeat(IR) border, codon bias, and phylogeny. The results showed that the whole chloroplast genome of A. lancea was 153 178 bp, with an 84 226 bp large single copy(LSC) and a 18 658 bp small single copy(SSC) separated by a pair of IRs(25 147 bp). The genome had the GC content of 37.7% and 124 genes: 87 protein-coding genes, 8 rRNA genes, and 29 tRNA genes. It had 26 287 codons and encoded 20 amino acids. Phylogenetic analysis showed that Atractylodes species clustered into one clade and that A. lancea had close genetic relationship with A. koreana. This study established a method for sequencing the chloroplast genome of A. lancea and enriched the genetic resources of Compositae. The findings are expected to lay a foundation for species identification, analysis of genetic diversity, and resource conservation of A. lancea.
Phylogeny
;
Atractylodes/genetics*
;
Genome, Chloroplast
;
Whole Genome Sequencing
;
Microsatellite Repeats
;
Lamiales
6.Screening of pathogenic molecular markers of Staphylococcus aureus in children based on whole genome sequencing technology.
Jian-Yu CHEN ; Xu-Lin WANG ; Wen-Yu LI ; Min-Qi CHEN ; Jun-Li ZHOU ; Zhen-Jiang YAO ; Jin-Jian FU ; Xiao-Hua YE
Chinese Journal of Contemporary Pediatrics 2023;25(11):1161-1169
OBJECTIVES:
To explore the molecular characteristics of Staphylococcus aureus (S. aureus) in children, and to compare the molecular characteristics of different types of strains (infection and colonization strains) so as to reveal pathogenic molecular markers of S. aureus.
METHODS:
A cross-sectional study design was used to conduct nasopharyngeal swab sampling from healthy children in the community and clinical samples from infected children in the hospital. Whole genome sequencing was used to detect antibiotic resistance genes and virulence genes. A random forest method to used to screen pathogenic markers.
RESULTS:
A total of 512 S. aureus strains were detected, including 272 infection strains and 240 colonization strains. For virulence genes, the carrying rates of enterotoxin genes (seb and sep), extracellular enzyme coding genes (splA, splB, splE and edinC), leukocytotoxin genes (lukD, lukE, lukF-PV and lukS-PV) and epidermal exfoliating genes (eta and etb) in infection strains were higher than those in colonization strains. But the carrying rates of enterotoxin genes (sec, sec3, seg, seh, sei, sel, sem, sen, seo and seu) were lower in infection strains than in colonization strains (P<0.05). For antibiotic resistance genes, the carrying rates of lnuA, lnuG, aadD, tetK and dfrG were significantly higher in infection strains than in colonization strains (P<0.05). The accuracy of cross-validation of the random forest model for screening pathogenic markers of S. aureus before and after screening was 69% and 68%, respectively, and the area under the curve was 0.75 and 0.70, respectively. The random forest model finally screened out 16 pathogenic markers (sem, etb, splE, sep, ser, mecA, lnuA, sea, blaZ, cat(pC233), blaTEm-1A, aph(3')-III, ermB, ermA, ant(9)-Ia and ant(6)-Ia). The top five variables in the variable importance ranking were sem (OR=0.40), etb (OR=3.95), splE (OR=1.68), sep (OR=3.97), and ser (OR=1.68).
CONCLUSIONS
The random forest model can screen out pathogenic markers of S. aureus and exhibits a superior predictive performance, providing genetic evidence for tracing highly pathogenic S. aureus and conducting precise targeted interventions.
Child
;
Humans
;
Staphylococcus aureus/genetics*
;
Cross-Sectional Studies
;
Enterotoxins/genetics*
;
Staphylococcal Infections
;
Whole Genome Sequencing
7.Comprehensive analysis of RNA-seq and whole genome sequencing data reveals no evidence for SARS-CoV-2 integrating into host genome.
Yu-Sheng CHEN ; Shuaiyao LU ; Bing ZHANG ; Tingfu DU ; Wen-Jie LI ; Meng LEI ; Yanan ZHOU ; Yong ZHANG ; Penghui LIU ; Yong-Qiao SUN ; Yong-Liang ZHAO ; Ying YANG ; Xiaozhong PENG ; Yun-Gui YANG
Protein & Cell 2022;13(5):379-385
9.Prenatal diagnosis of fetuses with renal anomalies by whole genome sequencing.
Fengchang QIAO ; Ping HU ; Cuiping ZHANG ; Yan WANG ; Ran ZHOU ; Chunyu LUO ; Zhengfeng XU
Chinese Journal of Medical Genetics 2022;39(8):819-823
OBJECTIVE:
To explore the genetic basis for fetuses with renal anomalies.
METHODS:
Genomic DNA of four fetuses and their parents was extracted from amniotic fluid and peripheral blood samples and subjected to whole genome sequencing. Candidate variants were predicted according to the American College of Medical Genetics and Genomics (ACMG) guidelines and validated by SNP-array and Sanger sequencing.
RESULTS:
Two fetuses were found to carry a 1.45 Mb pathogenic microdeletion in 17q12 and a pathogenic 1.85 Mb microduplication at 1q21.1-21.2, respectively. One fetus was found to harbor compound heterozygous variants c.8301del (p.Asn2768Thrfs*18) and c.4481del (p.Asn1494Thrfs*6) of the PKHD1 gene, which were predicted to be pathogenic. And one fetus has harbored homozygous c.1372dup (p.Thr458Asnfs*5) variants of the BBS12 gene, which was predicted to be likely pathogenic. All variants were validated by Sanger sequencing.
CONCLUSION
Whole genome sequencing can enable efficient prenatal diagnosis for fetuses with renal anomalies with high accuracy.
Female
;
Fetus/abnormalities*
;
Humans
;
Pregnancy
;
Prenatal Diagnosis
;
Whole Genome Sequencing
10.Estimation of molecular clock of Mycobacterium tuberculosis based on whole genome sequencing data.
Bi Lin TAO ; Yu Ting WANG ; Zhong Qi LI ; Ji Zhou WU ; Jian Ming WANG
Chinese Journal of Epidemiology 2022;43(9):1462-1468
Objective: To analyze the genomic mutation of Mycobacterium tuberculosis (M. tuberculosis) isolated in endogenous activation period and estimate the molecular clock based on the whole genome sequencing data. Methods: Literatures of the whole genome research of endogenous reactivated tuberculosis were retrieved, and the corresponding whole genome sequencing data were downloaded. We extracted the single nucleotide polymorphisms (SNPs) and strain isolation time of initial treatment and relapse of tuberculosis cases, explored the relationship between the different SNPs and interval between initial treatment and relapse by Poisson regression model, calculated the M. tuberculosis molecular clock, and estimated the mutation rate. Results: When the generation time of M. tuberculosis was 18 hours, the mutation rate in 0-2 years, i.e. short-term endogenous activation, was 6.47×10-10 (95%CI: 5.59×10-10-7.44×10-10), which was significantly higher than that in 2-14 years in long term endogenous activation (3.27×10-10, 95%CI: 2.88×10-10-3.69×10-10). The mutation rates of 0-, 1-, 2-, 3-, 5- and 7-14 years were 7.10×10-10, 6.06×10-10, 4.24×10-10, 5.34×10-10, 2.59×10-10 and 1.26×10-10 respectively. Conclusions: In the period of endogenous reactivation, the mutation rate of M. tuberculosis decreases with the interval time between initial treatment and relapse, which verifies the clinically observed phenomenon that the relapse often occurs within two years after the initial treatment of tuberculosis.
Genome, Bacterial
;
Humans
;
Mycobacterium tuberculosis/genetics*
;
Recurrence
;
Tuberculosis/microbiology*
;
Whole Genome Sequencing

Result Analysis
Print
Save
E-mail