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.Clinical significance of trisomy 7 signaled by non-invasive prenatal testing and a literature review.
Xinxin TANG ; Ting YIN ; Min CHEN ; Zhiwei WANG ; Yue ZHANG ; Fang ZHANG ; Yunqiu DU ; Yuhua SUN ; Leilei WANG
Chinese Journal of Medical Genetics 2025;42(1):12-17
OBJECTIVE:
To explore the clinical significance of trisomy 7 signaled by non-invasive prenatal testing (NIPT).
METHODS:
Pregnant women with high risk for trisomy 7 by NIPT from January 2017 to December 2023 were selected as the study subjects, and the results of prenatal diagnosis and follow-up were analyzed. Literature related to pregnant women with a high risk for trisomy 7 by NIPT from January 2016 to July 2024 was retrieved from China Biomedical Literature Database, Wanfang Database, China National Knowledge Infrastructure and PubMed database. Relevant information such as the incidence of trisomy 7 by NIPT, positive predictive value (PPV), and pregnancy outcomes were collected. This study has been approved by the Medical Ethics Committee of Lianyungang Maternal and Child Health Care Hospital (Ethics No. JS2022010).
RESULTS:
A total of 51 women with a high risk for trisomy 7 by NIPT were identified. Thirty-two of them had chosen chromosomal microarray analysis (CMA) of amniotic fluid cells, and 1 case of mosaic trisomy 7 was detected, which had yielded a PPV of 3.13%. Four women had opted termination of pregnancy, 1 had miscarriage, 4 had pre-term and/or low weight birth, whilst the remaining 42 (82.4%) had full-term delivery. In total 19 literature were retrieved, which had involved 278 cases of trisomy 7 signaled by NIPT, among which 5 fetuses with mosaic trisomy 7 (3.14%) were confirmed. Among the 211 women with follow-up outcomes, 2 (0.95%) had intrauterine growth restriction, 3 (1.42%) had abnormal fetal structure detected by ultrasound, 2 (0.95%) had miscarriage, 9 (4.27%) underwent pregnancy termination, 28 (13.27%) had preterm and/or low weight birth, whilst 167 (79.14%) had normal delivery. In 18 cases, chromosomal analysis of placental tissue was carried out, and 17 were confirmed to have mosaicism trisomy 7.
CONCLUSION
The PPV for trisomy 7 signaled by NIPT is extremely low. Although most of such women had a full term delivery, adverse pregnancy outcomes may still occur in a minority of cases. Clinicians should provide adequate genetic counseling for such women and recommend appropriate prenatal diagnosis strategies and optimal perinatal management plans.
Humans
;
Female
;
Pregnancy
;
Trisomy/diagnosis*
;
Chromosomes, Human, Pair 7/genetics*
;
Adult
;
Prenatal Diagnosis/methods*
;
Noninvasive Prenatal Testing/methods*
;
Pregnancy Outcome
;
Clinical Relevance
3.Genetic analysis of a Chinese pedigree with rare mosaic 11q partial duplication and a literature review.
Lili ZHOU ; Chenyang XU ; Hao WU ; Sheng HUANG ; Xueqin XU ; Xiaohua TANG
Chinese Journal of Medical Genetics 2025;42(1):94-101
OBJECTIVE:
To explore the genetic characteristics of a Chinese pedigree with rare mosaic 11q partial duplication and its pathogenetic mechanisms.
METHODS:
A pedigree which underwent prenatal diagnosis at Wenzhou Central Hospital between September 25, 2015 and November 30, 2023 was selected for the study. Clinical data were collected from the pedigree. Peripheral blood samples from the parents, amniotic fluid from the fetus, and peripheral blood sample from the neonate were obtained. Genetic testing was carried out by using G-banded chromosomal karyotyping and single nucleotide polymorphism array (SNP-array) technology. Relevant literature was searched in the CNKI, Wanfang Data Knowledge Service Platform, and PubMed databases to summarize the clinical phenotypes of patients with 11q partial duplication. This study was approved by the Medical Ethics Committee of Wenzhou Central Hospital (Ethics No. L2024-07-080).
RESULTS:
The pregnant woman (G3) had a history of adverse pregnancy outcomes. During her first pregnancy (G1), prenatal ultrasound indicated intrauterine growth restriction and a Dandy-Walker variant. Follow-up at 8 years of age showed developmental delays and mild intellectual disability. During her second pregnancy (G2), prenatal ultrasound revealed nasal bone hypoplasia, and the pregnancy was terminated at 23rd gestational week. During her third pregnancy (G3), all prenatal tests were normal, and the neonate showed normal growth and development at 4 months of age. The karyotype of amniotic fluid of her first pregnancy was 46,X?, and the SNP-array analysis of neonatal peripheral blood showed arr[GRCh37/hg19]11q13.4q25(70432450_134607121)×2~3, with a mosaicism rate being approximately 40%. The karyotype for her second pregnancy was 46,X?,rec(11)dup(11q)inv(11)(p15q13)dmat[6]/46,X?[27], and the SNP-array result was arr[GRCh38]11q13.4q25(71406636_135067522)×2~3, with a mosaicism rate being approximately 75%. The karyotype for her third pregnancy was 46,X?,inv(11)(p15q13)mat, and the SNP-array result was arr(XN)×1,(1~22)×2. The karyotype of the woman was 46,XX,inv(11)(p15q13), and that of her husband was 46,XY. A review of 12 similar cases (including G1) from the literature revealed that the common clinical phenotypes of 11q partial duplication included intellectual disability (12/12), developmental delay (12/12), ear abnormalities (12/12), microcephaly (10/12), seizures (8/12), hypotonia (8/12), and congenital heart malformations (7/12).
CONCLUSION
Mosaic partial duplication of 11q may underlie the genetic etiology of this pedigree. The pregnant woman is a carrier of an inversion on chromosome 11, which might have formed the mosaic 11q partial duplication through meiotic errors and mitotic trisomy rescue mechanisms during reproduction.
Adult
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Female
;
Humans
;
Male
;
Pregnancy
;
China
;
Chromosome Duplication
;
Chromosomes, Human, Pair 11/genetics*
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East Asian People/genetics*
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Karyotyping
;
Mosaicism
;
Pedigree
;
Polymorphism, Single Nucleotide
;
Prenatal Diagnosis
4.Results of screening and prenatal diagnosis for 71 fetuses with high risk for trisomy/monosomy 13 syndrome by non-invasive prenatal screening.
Peng DAI ; Ganye ZHAO ; Yanjie XIA ; Xiangdong KONG
Chinese Journal of Medical Genetics 2025;42(4):397-405
OBJECTIVE:
To analyze the clinical data and results of prenatal diagnosis for fetuses with high-risk for trisomy/monosomy 13 by non-invasive prenatal testing (NIPT).
METHODS:
Clinical data of pregnant women with fetus at a high risk for trisomy/monosomy 13 by NIPT at the First Affiliated Hospital of Zhengzhou University from May 2016 to May 2024 were reviewed, and relevant data such as Z-score, positive predictive value (PPV) and fetal fraction (FF) were analyzed to assess the correlation between them. This study was approved by the Ethics Committee of the Hospital (No. 2018-YB-08).
RESULTS:
71 fetuses were found to have a high risk by NIPT, including 58 cases for trisomy 13 (T13) and 13 cases for monosomy 13 (M13). 52 women had opted invasive prenatal diagnosis and 13 cases were confirmed, which yielded a positive prediction value (PPV) of 25%. 12 fetuses were confirmed as T13 (PPV = 29.3%; 12/41), 1 was confirmed as M13 (PPV = 9.1%; 1/11). The PPV had increased along with the Z-score. Fetal faction (FF) was not correlated with the age of woman but gestational age, and was negatively correlated with the body mass index. No statistical difference was found in FF and Z-score between true- and false-positive fetuses, and there was a weak correlation between the Z-score and FF. The PPV of the NIPT could be improved by combining the results of ultrasonography.
CONCLUSION
The high false positive rate for T13 may be related to confined placental mosaicism, PPV is related to the Z-score, which in turn is related to FF. High-risk women are strongly recommended to undergo genetic counseling and prenatal diagnosis. Clinicians should consider relevant information such as the age of women, gestational age, indication for prenatal screening, Z-score, PPV, and FF in order to accurately interpret the result of NIPT, reduce anxiety, and avoid direct termination of the pregnancy.
Humans
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Female
;
Pregnancy
;
Trisomy 13 Syndrome/genetics*
;
Adult
;
Prenatal Diagnosis/methods*
;
Noninvasive Prenatal Testing/methods*
5.Development and application of a digital PCR-based assay for rapid diagnosis of common fetal chromosomal aneuploidies.
Xuejiao CHEN ; Yanfeng YANG ; Yuanyuan YING ; Feiyan PAN ; Zhiqiang GU ; Weimeng JIAO ; Zehang HE ; Huihui XU
Chinese Journal of Medical Genetics 2025;42(5):592-596
OBJECTIVE:
To assess the clinical value of digital PCR (dPCR) for the prenatal diagnosis of common fetal aneuploidies.
METHODS:
A dPCR-based assay was developed for detecting trisomies 21, 18, and 13. A retrospective analysis was carried out on 173 amniotic fluid samples collected by the Prenatal Diagnosis Center of Taizhou Hospital between January 2017 and December 2023. By using chromosomal karyotyping as the gold standard, the diagnostic performance of the multiplex dPCR system was evaluated in a double-blind manner. This study has been approved by the Ethics Committee of Taizhou Hospital (Ethics No. K20250339).
RESULTS:
Chromosomal karyotyping has identified 59 cases of trisomy 21, 5 cases of trisomy 18, 2 cases of trisomy 13, 6 cases with chromosomal structural abnormalities or mosaicisms, and 101 cases with a normal karyotype. The dPCR results (Z-score cutoff = 4.0, CI = 99.997%) showed full concordance with karyotyping (sensitivity = 100%, specificity = 100%, Kappa = 1). Among the 6 structurally abnormal or mosaicism samples, dPCR has accurately detected 4 cases, but mis-classified 2 cases of trisomy 21 with very low-level mosaicisms (3.3%, 6.9%, respectively) as normal.
CONCLUSION
The established multiplex dPCR system demonstrated high diagnostic accuracy for common chromosomal aneuploidies, with results available within 24 hours. It can serve as an efficient supplementary tool to conventional chromosomal karyotyping, providing reliable support for time-sensitive clinical decision-making in prenatal diagnosis.
Humans
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Female
;
Pregnancy
;
Aneuploidy
;
Prenatal Diagnosis/methods*
;
Karyotyping
;
Retrospective Studies
;
Polymerase Chain Reaction/methods*
;
Chromosome Disorders/genetics*
;
Adult
;
Trisomy 13 Syndrome/diagnosis*
;
Trisomy 18 Syndrome/genetics*
;
Down Syndrome/genetics*
6.Analysis of the clinical outcomes of fetal 6p22.1-p21.32 duplications signaled by non-invasive prenatal screening.
Peng DAI ; Ganye ZHAO ; Yaqin HOU ; Shuang HU ; Xiangdong KONG
Chinese Journal of Medical Genetics 2024;41(12):1411-1415
OBJECTIVE:
To summarize the results of prenatal diagnosis and outcome of pregnancy of fetuses with a high risk for 6p22.1.1-p21.32 duplication signaled by non-invasive prenatal screening (NIPS).
METHODS:
Clinical information, results of prenatal diagnosis and pregnancy for fetuses with a high risk for 6p22.1-p21.32 duplication were collected and analyzed. This study has been approved by the Medical Ethics Committee of the First Affiliated Hospital of Zhengzhou University (Ethic No. 2018-YB-08).
RESULTS:
Forty three pregnant women with a high risk for 6p22.1-p21.32 duplication were identified by NIPS, among whom 30 had accepted invasive prenatal diagnosis, and 27 fetuses were verified to be false positive. Three fetuses were found to have other chromosomal abnormalities, among whom two were rated to be likely benign CNV and 1 was rated to be likely pathogenic. Follow up of the 43 pregnant women revealed that 35 fetuses were normal after birth, 1 pregnancy was terminated, and 7 were lost to follow up.
CONCLUSION
For pregnant women with a high risk for 6p22.1-p21.32 duplication signaled by NIPS, genetic counselor need to inform them the high false positive rate and recommend invasive prenatal diagnosis and/or ultrasound examination in order to reduce the psychological and economic burdens.
Humans
;
Female
;
Pregnancy
;
Chromosome Duplication
;
Adult
;
Prenatal Diagnosis/methods*
;
Chromosomes, Human, Pair 6/genetics*
;
Pregnancy Outcome
;
Noninvasive Prenatal Testing/methods*
;
Chromosome Disorders/genetics*
;
Fetus/abnormalities*
7.Clinical and genetic analysis of a case with 2p23.2p22.1 duplication.
Leilei GU ; Xiangyu ZHU ; Wei LIU ; Jie LI
Chinese Journal of Medical Genetics 2024;41(12):1491-1495
OBJECTIVE:
To report on the phenotype of an adult patient with 2p23.2p22.1 duplication and explore its genotype-phenotype correlation.
METHODS:
A pregnant woman who had presented at the Affiliated Drum Tower Hospital of Nanjing University Medical School on January 12, 2024 for a high risk signaled by NIPT was selected as the study subject. Amniotic fluid and peripheral blood samples were collected and subjected to chromosomal microarray analysis (CMA). The phenotype of the patient was observed, the medical history was taken, combined with the result of CMA assay, relevant database was searched for similar cases reported in the literature, and the correlation between genotype and phenotype was analyzed.
RESULTS:
The CMA result of the patient was arr[GRCh38]2p23.2p22.1(27961669_39280633)×3, which indicated a 11.31 Mb duplication. The woman was found to have short stature, learning disability, visual deficit, sleep disorder and other disorders.
CONCLUSION
The duplication of PPP1CB and SOS1 genes within the 2p23.2p22.1 region can result in Noonan syndrome-like clinical manifestations such as short stature and reduced visual acuity. The duplication of the PPP1CB gene may be associated with the abnormal visual phenotype.
Humans
;
Female
;
Chromosomes, Human, Pair 2/genetics*
;
Adult
;
Pregnancy
;
Chromosome Duplication
;
Phenotype
10.Genetic analysis of a fetus with mosaic trisomy 12 and severe heart defects and a literature review.
Ting YIN ; Zhiwei WANG ; Juan TAN ; Xinxin TANG ; Yongan WANG ; Ping HU ; Leilei WANG
Chinese Journal of Medical Genetics 2023;40(4):490-494
OBJECTIVE:
To explore the genetic basis for a fetus with severe heart defect and mosaic trisomy 12, and the correlation between chromosomal abnormalities and clinical manifestations and pregnancy outcome.
METHODS:
A 33-year-old pregnant woman who presented at Lianyungang Maternal and Child Health Care Hospital on May 17, 2021 due to abnormal fetal heart development revealed by ultrasonography was selected as the study subject. Clinical data of the fetus were collected. Amniotic fluid sample of the pregnant women was collected and subjected to G-banded chromosomal karyotyping and chromosomal microarray analysis (CMA). The CNKI, WanFang and PubMed databases were searched with key words, with the retrieval period set as from June 1, 1992 to June 1, 2022.
RESULTS:
For the 33-year-old pregnant woman, ultrasonography at 22+6 gestational weeks had revealed abnormal fetal heart development and ectopic pulmonary vein drainage. G-banded karyotyping showed that the fetus has a karyotype of mos 47,XX,+12[1]/46,XX[73], with the mosaicism rate being 1.35%. CMA results suggested that about 18% of fetal chromosome 12 was trisomic. A newborn was delivered at 39 weeks of gestation. Follow-up confirmed severe congenital heart disease, small head circumference, low-set ears and auricular deformity. The infant had died 3 months later. The database search has retrieved 9 reports. Literature review suggested that the liveborn infants with mosaic trisomy 12 had diverse clinical manifestations depending on the affected organs, which had included congenital heart disease and/or other organs and facial dysmorphisms, resulting in adverse pregnancy outcomes.
CONCLUSION
Trisomy 12 mosaicism is an important factor for severe heart defects. The results of ultrasound examination have important value for evaluating the prognosis of the affected fetuses.
Infant, Newborn
;
Child
;
Pregnancy
;
Female
;
Humans
;
Adult
;
Trisomy/genetics*
;
Amniocentesis/methods*
;
Chromosome Disorders
;
Mosaicism
;
Fetus
;
Heart Defects, Congenital/genetics*

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