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

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 investigate the X-chromosome inactivation (XCI) patterns and origin in four children with Rett syndrome (RTT), and to explore the genetic basis of their phenotypic variability. METHODS: Four pediatric RTT cases diagnosed at Northwest Women's and Children's Hospital between August 1, 2022 and October 31, 2024 were enrolled. Clinical data were collected, and whole exome sequencing (WES) and Sanger sequencing were performed on the children and their parents to identify pathogenic variants. XCI analysis and linkage studies were conducted to determine the origin of variants and assess skewed XCI. This study was approved by the Medical Ethics Committee of the Northwest Women's and Children's Hospital (Ethics No. 21-036). RESULTS: WES and Sanger sequencing revealed that the four children carried the following MECP2 (NM_001110792.2) variants. c.916C>T (p.Arg306Cys), c.842delG (p.G281Afs*20), c.763C>T (p.R255X), and c.686C>T (p.Pro229Leu). The c.916C>T variant was maternally inherited, while the other three were de novo. All four variants have been previously reported: c.916C>T, c.842delG, and c.763C>T were classified as pathogenic, whereas c.686C>T was deemed likely pathogenic. XCI analysis demonstrated skewed inactivation in child 2 and 3 and their mothers, with maternal X-chromosome recombination during gametogenesis observed in child 3. All variants were located on the maternal X chromosome. CONCLUSION Skewed XCI is a common pathogenic mechanism in MECP2-related RTT, and MECP2 variants may exhibit a maternal origin bias. Clinical evaluation should incorporate XCI status for comprehensive genetic analysis.
Child ; Humans ; Chromosomes, Human, X/genetics* ; Exome Sequencing ; Methyl-CpG-Binding Protein 2/genetics* ; Mutation ; Rett Syndrome/genetics* ; X Chromosome Inactivation/genetics*

OBJECTIVE: To explore the mechanism for the occurrence and phenotypic characteristics of Turner syndrome based on a prenatally diagnosed case of a mosaic karyotype containing double pseudo-isodicentric X chromosome and a review of relevant literature. METHODS: A fetus diagnosed with increased risk for trisomy 21 at the Provincial Hospital Affiliated to Shandong First Medical University in August 2023 was selected as the study subject. Clinical data of the fetus was collected. Following amniocentesis, chromosomal G-banding karyotype analysis and chromosomal microarray analysis (CMA) were carried out. This study has been approved by the Ethics Committee of the Hospital (Ethics No.: SWYX No. 2022-287). RESULTS: The early-trimester screening suggested a high risk of trisomy 21 (1/19), with free β-hCG of 116 ng/mL (MoM value 2.35), PAPP-A of 0.394 ng/mL (MoM value 0.12), and NT value of 1.3 mm, though no abnormality was found in the fetus at 19 weeks gestation. The karyotype of amniocyte was determined as 46,X,psu idic(X)(p11.21)[55]/45,X[27]/47,X,psu idic(X)(p11.21)×2[5]/46,XX[13]. CMA has yielded a result of arr[GRCh37] Xp22.33p11.21(168552_55585678)×1[0.67],Xp11.21q28(55703291_155233098)×3[0.5]. CONCLUSION Karyotypes of Turner syndrome are complex and diverse, and a rare 46,X,psu idic(X)(p11.21)[55]/45,X[27]/47,X,psu idic(X)(p11.21)×2[5]/46,XX[13] mosaic karyotype with double pseudo-isodicentric X chromosome has been identified. Literature review suggested that this karyotype may lead to phenotypic diversification and a risk of reduced sensitivity to hormone therapy.
Humans ; Turner Syndrome/diagnosis* ; Female ; Pregnancy ; Chromosomes, Human, X/genetics* ; Mosaicism ; Prenatal Diagnosis ; Karyotyping ; Adult ; Karyotype ; Amniocentesis

OBJECTIVE: To explore the clinical characteristics and genetic factors in four patients with Disorder of sex development (DSD). METHODS: Four patients who visited Tianjin Medical University General Hospital between January 2023 and January 2024, presenting with short stature, abnormal external genitalia, or infertility as their chief complaints, were selected as the study subjects. Clinical data were collected, and peripheral or umbilical cord blood samples were obtained for karyotyping analysis and low-depth whole-genome sequencing (CNV-seq). Quantitative fluorescence PCR (QF-PCR) was used to detect the sex-determining region Y (SRY) gene and azoospermia factor (AZF) on the Y chromosome, while fluorescence in situ hybridization (FISH) was employed to determine the location of the SRY gene. Whole exome sequencing (WES) was performed for genetic testing, and Sanger sequencing was used for familial validation of the candidate variants. The study procedure and protocol were approved by the Medical Ethics Committee of Tianjin Medical University General Hospital (Ethics No.: IRB2024-WZ-006). RESULTS: Case 1 had a karyotype of 45,X[22]/46,XY[8], with CNV-seq indicating a mosaic deletion of 7.44 Mb (copy number = 0.2) at Yp11.31-p11.2, a mosaic deletion of 5.32 Mb (copy number = 0.3) at Yq11.1-q11.221, and a deletion of 10.26 Mb (copy number = 0) at Yq11.221-q11.23. Y chromosome microdeletion analysis showed SRY and AZFa (+), AZFb+c (-). Case 2 had a karyotype of 45,X[12]/46,X,del(X)(q26.3)[18], with CNV-seq indicating a mosaic deletion of 132.62 Mb (copy number = 1.4) at Xp22.33-q26.3 and a deletion of 19.62 Mb (copy number = 1) at Xq26.3-q28. Case 3 had a karyotype of 46,XX, with CNV-seq showing two copies of the X chromosome and no Y chromosome. Y chromosome microdeletion analysis showed SRY (+) and AZFa+b+c (-), and FISH confirmed a translocation of the SRY gene to the terminal end of the short arm of the X chromosome. Case 4 had a karyotype of 46,XY, with CNV-seq showing one copy each of the X and Y chromosomes. Y chromosome microdeletion analysis showed SRY(+) and AZFa+b+c (+), and WES revealed a c.1103del variant in the AR gene (maternal origin), which was classified as a pathogenic variant based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) (PVS1+PP1+PM2_Supporting). CONCLUSION The combined application of multiple detection techniques such as chromosomal karyotyping analysis, CNV-seq, QF-PCR, and WES can identify the genetic etiology of DSD patients, providing a basis for clinical consultation and treatment plan formulation.
Humans ; Male ; Female ; Chromosomes, Human, Y/genetics* ; Disorders of Sex Development/genetics* ; Sex-Determining Region Y Protein/genetics* ; Karyotyping ; In Situ Hybridization, Fluorescence ; Exome Sequencing ; Adult ; Child

Y chromosome microdeletions are an important cause of male infertility. At present, research on the Y chromosome is mainly focused on analyzing the loss of large segments of the azoospermia factor a/b/c (AZFa/b/c) gene, and few studies have reported the impact of unit point deletion in the AZF band on fertility. This study analyzed the effect of sperm quality after sY1192 loss in 116 patients. The sY1192-independent deletion accounted for 41.4% (48/116). Eight patterns were found in the deletions associated with sY1192. The rate of sperm detection was similar in the semen of patients with the independent sY1192 deletion and the combined sY1192 deletions (52.1% vs 50.0%). The patients with only sY1192 gene loss had a higher probability of sperm detection than the patients whose sY1192 gene locus existed, but other gene loci were lost (52.1% vs 32.0%). The hormone levels were similar in patients with sY1192 deletion alone and in those with sY1192 deletion and other types of microdeletions in the presence of the sY1192 locus. After multiple intracytoplasmic sperm injection (ICSI) attempts, the pregnancy rate of spouses of men with sY1192-independent deletions was similar to that of other types of microdeletions, but the fertilization and cleavage rates were higher. We observed that eight deletion patterns were observed for sY1192 microdeletions of AZFb/c, dominated by the independent deletion of sY1192. After ICSI, the fertilization rate and cleavage rate of the sY1192-independent microdeletion were higher than those of other Y chromosome microdeletion types, but there was no significant difference in pregnancy outcomes.
Humans ; Female ; Pregnancy ; Male ; Chromosomes, Human, Y/genetics* ; Adult ; Chromosome Deletion ; Pregnancy Outcome/genetics* ; Infertility, Male/genetics* ; Spermatozoa/physiology* ; Semen Analysis ; Sex Chromosome Disorders of Sex Development/genetics* ; Sperm Injections, Intracytoplasmic ; Azoospermia/genetics* ; Sex Chromosome Aberrations

Klinefelter syndrome (KS) is the most common genetic cause of human male infertility. However, the effect of the extra X chromosome on different testicular cell types remains poorly understood. Here, we profiled testicular single-cell transcriptomes from three KS patients and normal karyotype control individuals. Among the different somatic cells, Sertoli cells showed the greatest transcriptome changes in KS patients. Further analysis showed that X-inactive-specific transcript ( XIST ), a key factor that inactivates one X chromosome in female mammals, was widely expressed in each testicular somatic cell type but not in Sertoli cells. The loss of XIST in Sertoli cells leads to an increased level of X chromosome genes, and further disrupts their transcription pattern and cellular function. This phenomenon was not detected in other somatic cells such as Leydig cells and vascular endothelial cells. These results proposed a new mechanism to explain why testicular atrophy in KS patients is heterogeneous with loss of seminiferous tubules but interstitial hyperplasia. Our study provides a theoretical basis for subsequent research and related treatment of KS by identifying Sertoli cell-specific X chromosome inactivation failure.
Animals ; Humans ; Male ; Female ; Sertoli Cells/metabolism* ; Klinefelter Syndrome/genetics* ; Endothelial Cells ; Testis/metabolism* ; X Chromosome/metabolism* ; Mammals/genetics*

OBJECTIVE: To investigate the clinical features and genetic etiology of a case of Turner syndrome (TS) with rapidly progressive puberty. METHODS: A child who had presented at the Pediatric Endocrinology Clinic of the Shenzhen People's Hospital on January 19, 2022 was selected as the study subject. Clinical data of the child were collected. Peripheral blood sample of the child was subjected to chromosomal microarray analysis (CMA) and multiple ligation-dependent probe amplification (MLPA). Previous studies related to TS with rapidly progressive puberty were retrieved from the CNKI, Wanfang Data Knowledge Service Platform, Boku, CBMdisc and PubMed databases with Turner syndrome and rapidly progressive puberty as the keywords. The duration for literature retrieval was set from November 9, 2021 to May 31, 2022. The clinical characteristics and karyotypes of the children were summarized. RESULTS: The child was a 13-year-and-2-month-old female. She was found to have breast development at 9, short stature at 10, and menarche at 11. At 13, she was found to have a 46,X,i(X)(q10) karyotype. At the time of admission, she had a height of 143.5 cm (< P3), with 6 ~ 8 nevi over her face and right clavicle. She also had bilateral simian creases but no saddle nasal bridge, neck webbing, cubitus valgus, shield chest or widened breast distance. She had menstruated for over 2 years, and her bone age has reached 15.6 years. CMA revealed that she had a 58.06 Mb deletion in the Xp22.33p11.1 region and a 94.49 Mb duplication in the Xp11.1q28 region. MLPA has confirmed monosomy Xp and trisomy Xq. A total of 13 reports were retrieved from the CNKI, Wanfang Data Knowledge Service Platform, Boku, CBMdisc and PubMed databases, which had included 14 similar cases. Analysis of the 15 children suggested that their main clinical manifestations have included short stature and growth retardation, and their chromosomal karyotypes were mainly mosaicisms. CONCLUSION The main clinical manifestations of TS with rapidly progressive puberty are short stature and growth retardation. Deletion in the Xp22.33p11.1 and duplication in the Xp11.1q28 probably underlay the TS with rapid progression in this child, which has provided a reference for clinical diagnosis and genetic counselling for her.
Humans ; Female ; Adolescent ; Puberty ; Turner Syndrome/genetics* ; Chromosomes, Human, X ; Karyotyping

OBJECTIVE: To explore the characteristics of copy number variation (CNV) within the Y chromosome azoospermia factor (AZF) region in patients with spermatogenesis disorders in the Shenzhen area. METHODS: A total of 123 patients with spermatogenesis disorders who had visited Shenzhen People's Hospital from January 2016 to October 2022 (including 73 patients with azoospermia and 50 patients with oligozoospermia) and 100 normal semen males were selected as the study subjects. The AZF region was detected with multiplex ligation-dependent probe amplification (MLPA), and the correlation between the CNV in the AZF region and spermatogenesis disorders was analyzed using the chi-square test or Fisher's exact test. RESULTS: 19 CNV were detected among 53 patients from the 223 samples, including 20 cases (27.40%, 20/73) from the azoospermia group, 19 cases (38%, 19/50) from the oligozoospermia group, and 14 cases (14%, 14/100) from the normal control group. In the azoospermia, oligozoospermia, and normal control groups, the detection rates for CNV related to the AZFa region (including AZFab and AZFabc) were 5.48% (4/73), 2.00% (1/50), and 0 (0/100), respectively. The detection rates for the AZFb region (including the AZFbc region) were 6.85% (5/73), 0 (0/50), and 0 (0/100), respectively. The detection rates for gr/gr deletions in the AZFc region were 2.74% (2/73), 6.00% (3/50), and 9.00% (9/100), respectively, and those for b2/b4 deletions in the AZFc region were 2.74% (2/73), 10.00% (5/50), and 0 (0/100), respectively. The detection rates for complex rearrangements in the AZFc region were 6.85% (5/73), 18.00% (9/50), and 3.00% (3/100), respectively. Statistical analysis showed no significant difference in the detection rate of gr/gr deletions between the three groups (Fisher's Exact Test value = 2.712, P = 0.249); the differences in the detection rate of b2/b4 deletions between the three groups were statistically significant (Fisher's Exact Test value = 9.489, P = 0.002); the differences in the detection rate of complex rearrangements in the AZFc region between the three groups were statistically significant (Fisher's Exact Test value = 9.493, P = 0.006). In this study, a rare AZFa region ARSLP1 gene deletion (involving SY86 deletion) was detected in a patient with oligozoospermia. CONCLUSION CNV in the AZFa and AZFb regions have a severe impact on spermatogenesis, but partial deletion in the AZFa region (ARSLP1 gene deletion) has a minor impact on spermatogenesis. The b2/b4 deletion and complex rearrangement in the AZFc region may be risk factors for male infertility. The gr/gr deletion may not serve as a risk factor for male infertility in the Shenzhen area.
Humans ; Male ; Azoospermia/genetics* ; DNA Copy Number Variations ; Oligospermia/genetics* ; Infertility, Male/genetics* ; Y Chromosome

OBJECTIVE: To carry out prenatal diagnosis for a fetus with mosaicism Yq deletion. METHODS: A fetus with high risk of sex chromosomes indicated by non-invasive prenatal testing (NIPT) at Tianjin Medical University General Hospital in July 2021 was selected as the study subject. Prenatal diagnosis of the fetus was performed with combined G-banded chromosomal karyotyping, fluorescence in situ hybridization (FISH), copy number variation sequencing (CNV-seq), real-time fluorescence PCR (QF-PCR), and ultrasound examination. RESULTS: Analysis of the amniocytes at 23 gestational weeks had yielded a 45,X karyotype. However, FISH had shown signals of Y chromosome. Re-examination by cordocentesis had shown a mosaicism of 46,X,+mar[33]/45,X[17]. FISH showed that 69% of the cells had contained Y chromosome signals. The result of CNV-seq was seq[19]del(Y)(q11.1q12)(mos) chrY: g.13200001_ 28820000del (mosaicism rate = 64%), which suggested mosaicism for a Yq deletion, which encompassed the azoospermia factor (AZF) region. Deletion of the AZF region was verified by QF-PCR. The fetal karyotype was ultimately determined as mos46,X,del(Y)(q11.1)[33]/45,X[17]. Although ultrasound examination had shown no abnormality in the fetus, the couple had opted to terminate the pregnancy, and the induced fetus had a normal male appearance. CONCLUSION The combined use of multiple techniques is beneficial for accurate and rapid prenatal diagnosis. For fetuses with mosaicism chromosomal abnormalities, it may be difficult to accurately predict the postnatal phenotype. It is therefore necessary to further explore their genotype-phenotype correlation in order to provide better guidance upon genetic counseling.
Female ; Pregnancy ; Male ; Humans ; Mosaicism ; DNA Copy Number Variations ; In Situ Hybridization, Fluorescence ; Y Chromosome ; Fetus