1.Prenatal diagnosis of 22q11.2 microduplication syndrome in a three-generation family: Clinical-genetic characteristics and literature review.
Yifan LIAO ; Yidong WEN ; Xiaoqin DENG ; Cimo WANG ; Zhirong SHANG ; Jinghong YANG ; Jiabing LI
Chinese Journal of Medical Genetics 2026;43(1):57-63
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
2.Precise identification of a cryptic balanced translocation in a couple with recurrent spontaneous abortions using C-MoKa technique.
Rui FAN ; Yaru LIU ; Tingting JI ; Xiaojuan XU ; Xuening DING ; Xiaoling MA
Chinese Journal of Medical Genetics 2026;43(1):64-69
OBJECTIVE:
Chromosome conformation-based karyotype analysis (C-MoKa) technology was used to test a couple who had experienced multiple adverse pregnancies in order to provide them with genetic counseling and reproductive guidance.
METHODS:
A couple presented at the Reproductive Medicine Center of the First Hospital of Lanzhou University in 2023 was selected as the study subject. Through C-MoKa testing, copy number variation sequencing (CNV-seq), and preimplantation genetic testing for aneuploidy (PGT-A), it was found that the couple's repeatedly miscarried fetuses and abnormal embryos exhibited highly similar chromosomal structural abnormalities. Using C-MoKa, the potential genetic abnormalities in both partners were traced, and reproductive guidance was provided based on the result. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: LDYYSZLLKH2025-09).
RESULTS:
CNV-seq analysis of the couple's miscarriage fetal chorionic villi showed del(18)(q21.2q23)(28.90 Mb) and dup(13)(q31.2q34)(26.26 Mb). Chromosomal karyotyping analysis of both partners showed no abnormality. From 2024 to 2025, the couple underwent three rounds of PGT-A assisted reproduction. The first embryo test showed del(13)(q31.2q34)(26.77 Mb) and dup(18)(q21.2q23)(29.08 Mb). The second embryo test showed dup(13)(q31.2q34)(26.26 Mb) and del(18)(q21.2q23)(28.90 Mb). And the third embryo test results showed complex chromosomal abnormalities. In 2025, after genetic counseling, the couple had opted C-MoKa test, which has detected no abnormality in the wife, but a balanced 46,XY,t(13;18)(q31.2;q21.2) translocation in the husband.
CONCLUSION
As a high-throughput sequencing method based on the three-dimensional conformation of chromatin, C-MoKa has the advantages of high resolution and high accuracy, and can accurately detect balanced translocations with similar banding patterns. It has therefore offered a powerful new tool for chromosomal analysis.
Female
;
Humans
;
Male
;
Pregnancy
;
Abortion, Habitual/genetics*
;
DNA Copy Number Variations
;
Karyotyping/methods*
;
Preimplantation Diagnosis
;
Translocation, Genetic
3.Prenatal phenotype and genetic analysis of two fetuses with Osteocraniostenosis due to variants of FAM111A gene.
Lingyi ZHANG ; Zhigang ZHANG ; Xingguang WANG ; Yanyan LI
Chinese Journal of Medical Genetics 2026;43(2):96-101
OBJECTIVE:
To investigate the prenatal manifestation and genetic basis for two fetuses suspected for Osteocraniostenosis (OCS).
METHODS:
Two fetuses undergoing invasive prenatal diagnosis at Cangzhou People's Hospital in April and August 2021 for short long bones and abnormal skull morphology were selected as the study subjects. Clinical data were collected and analyzed. Genomic DNA was extracted from amniotic fluid and peripheral blood samples of the two couples. Candidate variants were validated by Sanger sequencing. Literature was retrieved from CNKI, Wanfang Data Knowledge Service Platform and PubMed using keywords including "FAM111A gene", "gracile bone dysplasia", "FAM111A" and "osteocraniostenosis" from January 1, 2000 to June 30, 2025. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: K2020-049).
RESULTS:
Fetus 1 was found to have short limbs, abnormal skull morphology and shallow cerebral sulci. Fetus 2 showed short limbs, irregular skull halo, prominent forehead and bilateral frontal narrowing. Trio-WES revealed that fetus 1 has carried a heterozygous missense variant c.1582G>C (p.Asp528His) in exon 4 of the FAM111A gene, which was unreported previously. Fetus 2 has harbored a heterozygous in-frame deletion c.1020_1022delTTC (p.Ser343del) in exon 6 of the FAM111A gene, which has been recorded as likely pathogenic by the ClinVar and HGMD databases. Sanger sequencing confirmed that the parents of both fetuses were wild-type for the variant sites. A total of 9 previously reported patients with FAM111A-related gracile bone dysplasia/OCS from 4 publications were retrieved. The main clinical features included intrauterine growth restriction, hypomineralized skull, gracile long bones with narrow medullary cavities and characteristic facial anomalies, which were in large in keeping with the prenatal features of the two fetuses.
CONCLUSION
Both fetuses were diagnosed with FAM111A-related OCS based on the characteristic prenatal findings and identification of the FAM111A variants. Above finding expanded the phenotypic spectrum of FAM111A-associated disorders and provided clues for the prenatal diagnosis and genetic counseling.
Humans
;
Female
;
Pregnancy
;
Prenatal Diagnosis
;
Phenotype
;
Fetus
;
Male
;
Bone Diseases, Developmental/genetics*
;
Adult
4.Genetic analysis and prenatal diagnosis of structural brain abnormalities associated with TUBB gene c.155A>G variant.
Yifan LIU ; Wei SONG ; Xinlian WANG ; Yan RUAN ; Meng ZHANG ; Yujiao CHEN ; Yan LIU ; Puqing ZHANG ; Li WANG ; Yousheng YAN
Chinese Journal of Medical Genetics 2026;43(2):136-142
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
5.Genetic analysis of two cases of submicroscopic chromosomal structural variants leading to abnormal pregnancies.
Chengxiu XIE ; Xiong ZHU ; Yacong WANG ; Qingsong LIU
Chinese Journal of Medical Genetics 2026;43(2):143-150
OBJECTIVE:
To investigate the genetic mechanism for adverse pregnancies due to submicroscopic chromosomal structural variants in two cases, and to provide a precise guidance for preimplantation genetic testing.
METHODS:
Two families who had visited Chengdu Women's and Children's Central Hospital for reproduction guidance due to recurrent miscarriages, adverse pregnancy history and abnormal genetic testing of the offspring in June and December 2023 were selected as the study subjects. Chromosomal karyotyping and optical genome mapping (OGM) were carried out on peripheral blood samples from the two couples, and preimplantation genetic testing for structural rearrangement (PGT-SR) were performed on the blastocyst trophoblasts. This study was approved by the Medical Ethics Committee of the Hospital (Ethic No.: 2023-23).
RESULTS:
No abnormality was found on the G-banded karyotyping analysis for both couples. The OGM results revealed that the female partner of couple 1 had a translocation between 4pter-p16.3 (3.99 Mb) and 11pter-p15.4 (2.66 Mb), whilst no abnormality was found in the male partner. Similarly, the male partner of couple 2 had a translocation between 19q13.43-qter (1.90 Mb) and 22q13.31-qter (3.34 Mb). No abnormality was found in the female partner of couple 2. Neither breakpoints nor the adjacent region had involved an OMIM gene, except the formation of a fusion gene ZIM2-AS1-Z82186.1 (Both genes are non-coding, and the fusion gene was deemed as variant of unknown significance). PGT-SR of 11 blastocysts derived from couple 1 revealed that one embryo was suitable for priority transfer, three embryos were suitable for transfer, one embryo was recommended for genetic counselling, and six embryos were unsuitable for the transfer. For couple 2, six blastocysts were tested, of which only one embryo was deemed suitable for transfer.
CONCLUSION
When genetic testing of offspring indicates copy number variations such as deletions, duplications or mosaicism, the high-resolution OGM technique can be selected to screen parents for submicroscopic chromosomal structural variations. The result can facilitate accurate assessment for the risk of recurrence in offspring, selection of suitable method for reproduction, and identifying targets for PGT.
Humans
;
Female
;
Pregnancy
;
Adult
;
Male
;
Karyotyping
;
Chromosome Aberrations
;
Abortion, Habitual/genetics*
;
Preimplantation Diagnosis
;
Genetic Testing
6.Application of artificial intelligence-assisted chromosome karyotyping analysis in prenatal diagnosis of chromosomal mosaicism.
Ling ZHAO ; Shiwei SUN ; Qinghua ZHENG ; Qing YU ; Chongyang ZHU ; Ling LIU ; Yueli WU
Chinese Journal of Medical Genetics 2026;43(3):180-187
OBJECTIVE:
To explore the application value of artificial intelligence (AI)-assisted chromosomal karyotype analysis in the diagnosis of prenatal chromosomal mosaicism.
METHODS:
A retrospective analysis was conducted on 172 pregnant women who underwent amniocentesis at the Department of Medical Genetics and Prenatal Diagnosis, the Third Affiliated Hospital of Zhengzhou University between January 2019 and December 2024. All cases whose fetuses were diagnosed with chromosomal mosaicism via karyotype analysis and stratified into two groups based on the analytical software employed: the conventional analysis group (n = 70), which utilized Leica analysis software for karyotype image recognition and cell counting; and the AI-assisted analysis group (n = 102), which utilized AI-assisted software for the same procedures. The clinical performance of AI-assisted karyotype analysis in diagnosing chromosomal mosaicism was comprehensively evaluated by comparing the types of mosaic karyotypes, distribution of mosaic ratios, and verification outcomes of different detection modalities between the two groups. This study was approved by the Medical Ethics Committee of the Third Affiliated Hospital of Zhengzhou University (Ethics No.: 2024-406-01).
RESULTS:
No statistically significant difference was observed in baseline characteristics (maternal age, gestational week, and indications for prenatal diagnosis) between the two groups. Regarding the detection efficacy for numerical and structural mosaicisms, no significant difference was found in the detection of numerical mosaicism. However, the conventional analysis group exhibited a significantly higher detection rate of autosomal structural mosaicism compared to the AI-assisted group (11.43% vs. 0.98%, P < 0.05). Numerical mosaicism cases were further verified using copy number variation sequencing (CNV-seq) and/or fluorescence in situ hybridization (FISH). The AI-assisted group demonstrated a significantly lower inconsistency rate (5.56% vs. 20.41%, P < 0.05) compared to the conventional group. For low-proportion (< 10%) chromosomal mosaicism, the AI-assisted group had a significantly lower detection rate (13.25% vs. 29.69%, P < 0.05). Subsequent validation of low-proportion mosaicism by CNV-seq and/or FISH showed a higher consistency rate in the AI-assisted group (81.82% vs. 54.55%), though the difference did not reach statistical significance (P = 0.360).
CONCLUSION
For the karyotyping analysis of prenatal chromosomal mosaicism, AI-assisted karyotype analysis shows high accuracy and consistency in identifying numerical chromosomal mosaicism, particularly in reducing the detection of low-proportion (< 10%) mosaicism while improving verification accuracy. AI-assisted analysis can significantly improve the detection accuracy of numerical mosaicism and mitigate the risk of misclassification for low-proportion (< 10%) mosaicism, thereby providing more precise clinical evidence for the prenatal diagnosis of chromosomal mosaicisms.
Humans
;
Female
;
Mosaicism
;
Pregnancy
;
Karyotyping/methods*
;
Artificial Intelligence
;
Prenatal Diagnosis/methods*
;
Adult
;
Retrospective Studies
;
Chromosome Disorders/genetics*
;
Amniocentesis
7.From prenatal screening to passive diagnosis in adulthood: Phenotypic association analysis of 224 patients with Klinefelter syndrome.
Huanhuan ZHANG ; Yong WU ; Yamei XIE ; Qingsong LIU
Chinese Journal of Medical Genetics 2026;43(3):188-196
OBJECTIVE:
To investigate the detection patterns, clinical phenotypic characteristics, and differences in diagnostic timeliness of Klinefelter syndrome (KS) across prenatal and postnatal stages, with an aim to provide a basis for optimizing strategies for early screening, diagnosis, and intervention.
METHODS:
A retrospective study was conducted to analyze data from two phases. The prenatal diagnosis group included 33,302 pregnant women who underwent amniocytic karyotyping due to advanced maternal age, abnormal ultrasound findings, or high-risk non-invasive prenatal testing (NIPT). The postnatal diagnosis group included 52,101 patients who underwent peripheral blood karyotyping due to primary infertility, abnormal external genitalia, or growth and developmental abnormalities. Additionally, medical histories of adult diagnosed patients were reviewed retrospectively to identify early occult symptoms. This study was approved by the Medical Ethics Committee of Chengdu Women's and Children's Central Hospital (Ethics No.: LCYJ-2025-030).
RESULTS:
In the prenatal group, 96 cases of KS were detected (detection rate 0.29%). The primary indications for referral were NIPT indicating sex chromosome abnormalities (45.83%), advanced maternal age (16.66%), and ultrasound abnormalities (17.70%). In the postnatal group, 128 cases of KS were detected (detection rate 0.25%). Clinical presentations were primarily primary infertility/azoospermia (77.34%), and the patients were predominantly adults (84.40%). Retrospective analysis revealed that adult patients presented with specific physical signs that had been overlooked during childhood.
CONCLUSION
As KS lacks typical early clinical manifestations, diagnosis is often delayed until adulthood when reproductive needs arise, showing a pattern of "passive detection" and resulting in missed opportunities for optimal intervention. By conducting a comparative analysis of prenatal diagnostic data and postnatal retrospective data, a risk association model linking prenatal screening indications with childhood-specific signs was developed. This study has provided empirical evidence for establishing a multidisciplinary, full life-cycle management system of "screening ~ diagnosis ~ monitoring ~ intervention" helping to shift from "passive detection in adulthood" to "proactive management across the entire life course," and laid a foundation for improving early diagnosis rate and long-term quality of life for patients.
Humans
;
Klinefelter Syndrome/genetics*
;
Female
;
Adult
;
Pregnancy
;
Retrospective Studies
;
Prenatal Diagnosis/methods*
;
Male
;
Phenotype
;
Karyotyping
;
Young Adult
;
Adolescent
;
Middle Aged
8.Genetic analysis and reproductive intervention for 46 Chinese pedigrees affected with Hereditary multiple exostoses.
Lilan SU ; Xiao HU ; Jing DAI ; Zhengxing WAN ; Duo YI ; Shuangfei LI ; Liang HU ; Yueqiu TAN ; Fei GONG ; Ge LIN ; Guangxiu LU ; Qianjun ZHANG ; Juan DU ; Wenbin HE
Chinese Journal of Medical Genetics 2026;43(4):253-258
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
9.Clinical and genetic analysis of children with Silver-Russell syndrome.
Liming ZHANG ; Guimei PAN ; Dongxia FU ; Xue WU ; Yongxing CHEN
Chinese Journal of Medical Genetics 2026;43(4):259-264
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
10.Research on the screening efficiency of Thalassemia based on an automated evaluation software.
Jun HU ; Huan LIANG ; Limei DUAN ; Jianqiang GAO
Chinese Journal of Medical Genetics 2026;43(4):281-287
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

Result Analysis
Print
Save
E-mail