Disorders of sex development (DSD) are characterized by atypical development of chromosomal, gonadal, or phenotypic sex. 45X,46XY mosaicism is a type of sex chromosome DSD which presents with a wide heterogeneity of manifestations. We report the case of a 13-year-old phenotypically female who presented with clitoromegaly at puberty. Testosterone level was elevated on serology. Out of the 50 cells examined, 43 cells had Monosomy X while 7 cells had a normal male karyotype. She was managed by a multidisciplinary team. Due to the presence of Y chromosome, the solid nodular structure seen on the right gonad in magnetic resonance imaging and the pain caused by the phallus, Laparoscopic bilateral gonadectomy, salpingectomy and clitoroplasty were done after a shared decision making. Histopathology revealed Gonadoblastoma and Germ cell neoplasia-in-situ of the right gonad justifying timely removal. She was then maintained on estrogen for induction of secondary sexual characteristics.

Proteus syndrome (PS) is a mosaic disorder characterized by asymmetric overgrowth of a variety of tissues. Diagnostic criteria established in 1999 emphasized the mosaic distribution of lesions, progressive course, and disproportionate overgrowth. We present a case of proteus syndrome in a 12-year-old Filipino male with 9 year-history of enlargement of the left foot with soft, non-tender mass on the sole with a brain-like surface. Skin punch biopsy of the mass showed cerebriform connective tissue nevi which is pathognomonic of PS.

PS is a very rare disease with prevalence of less than 1 in 1,000,000 live births. Management of PS is extremely challenging, owing to the combination of the individuality of each case, the severity of the disease, and the risks of complications from procedures. A multidisciplinary clinical approach is strongly recommended to obtain the best possible management plans for individual patients.

OBJECTIVE: To retrospectively analyze sex chromosomal abnormalities and clinical manifestations of children with disorders of sex development (DSD). METHODS: A total of 14 857 children with clinical features of DSD including short stature, cryptorchidism, hypospadia, buried penis and developmental delay were recruited from Zhengzhou Children's Hospital from January 2013 to March 2022. Fluorescence in situ hybridization (FISH) and chromosomal karyotyping were carried out for such children. RESULTS: In total 423 children were found to harbor sex chromosome abnormalities, which has yielded a detection rate of 2.85%. There were 327 cases (77.30%) with Turner syndrome and a 45,X karyotype or its mosaicism. Among these, 325 were females with short stature as the main clinical manifestation, 2 were males with short stature, cryptorchidism and hypospadia as the main manifestations. Sixty-two children (14.66%) had a 47,XXY karyotype or its mosaicism, and showed characteristics of Klinefelter syndrome (KS) including cryptorchidism, buried penis and hypospadia. Nineteen cases (4.49%) had sex chromosome mosaicisms (XO/XY), which included 11 females with short stature, 8 males with hypospadia, and 6 cases with cryptorchidism, buried penis, testicular torsion and hypospadia. The remainder 15 cases (3.55%) included 9 children with a XYY karyotype or mosaicisms, with main clinical manifestations including cryptorchidisms and hypospadia, 4 children with a 47,XXX karyotype and clinical manifestations including short stature and labial adhesion, 1 child with a 46,XX/46,XY karyotype and clinical manifestations including micropenis, hypospadia, syndactyly and polydactyly, and 1 case with XXXX syndrome and clinical manifestations including growth retardation. CONCLUSION Among children with DSD due to sex chromosomal abnormalities, sex chromosome characteristics consistent with Turner syndrome was most common, among which mosaicism (XO/XX) was the commonest. In terms of clinical manifestations, the females mainly featured short stature, while males mainly featured external genital abnormalities. Early diagnosis and treatment are particularly important for improving the quality of life in such children.
Humans ; Male ; Female ; Turner Syndrome/genetics* ; In Situ Hybridization, Fluorescence ; Cryptorchidism ; Hypospadias ; Retrospective Studies ; Quality of Life ; Sex Chromosome Aberrations ; Karyotyping ; Mosaicism ; Disorders of Sex Development/genetics*

OBJECTIVE: To assess the value of combined copy number variation sequencing (CNV-seq) and chromosomal karyotyping for the diagnosis of amniocytic mosaicisms, in addition with a literature review. METHODS: Forty cases of amniocytic mosaicisms detected at the Genetic and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2021, in addition with 245 mosaicisms retrieved from 11 recent literature were evaluated in terms of detection rate, consistency rate, and pregnancy outcomes. RESULTS: The detection rate of amniocytic mosaicisms was 0.46% (40/8 621) in our center. And its consistency rate with chromosomal karyotyping was 75.0% (30/40). After genetic counseling, 30 (75.0%) couples had opted to terminate the pregnancy, 5 (12.5%) had decided to continue with the pregnancy, 3 (7.5%) fetuses were born alive, and 2 cases (5.0%) were lost in touch. By contrast, 245 cases (0.39%) of mosaicisms were identified among 63 577 amniotic samples, with a consistency rate of 62.8% (103/164) with other techniques. Among these, 114 cases (55.1%) were terminated, 75 (36.2%) were born alive, and 18 (8.7%) were lost during the follow up. CONCLUSION Combined CNV-seq and chromosomal karyotyping has a high value for the detection of amniotic mosaicisms.
Pregnancy ; Female ; Humans ; Mosaicism ; Chromosome Disorders/genetics* ; DNA Copy Number Variations ; Chromosome Aberrations ; Karyotyping ; Prenatal Diagnosis/methods*

OBJECTIVE: To investigate the perinatal clinical phenotype and genetic characteristics of two fetuses with ring chromosome 21 mosaicisms. METHODS: Two fetuses who were diagnosed at the Xiamen Maternal and Child Health Care Hospital in November 2021 were selected as the study subjects. Clinical data of the two fetuses were collected. Conventional G-banded karyotyping and chromosomal microarray analysis (CMA) were carried out for the fetuses and their parents. RESULTS: Prenatal ultrasonography of fetus 1 has revealed absence of nasal bone, ventricular septal defect, persistent left superior vena cava, and mild tricuspid regurgitation. Chromosomal karyotyping was 46,X?,dic r(21;21)(p12q22;q22p12)[41]/45,X?,-21[9]. CMA has revealed a 30.00 Mb quadruplication at 21q11.2q22.3 and a 3.00 Mb deletion at 21q22.3. For fetus 2, ultrasonography has revealed pointed echo of the nasal bone. The fetus was found to have a karyotype of 46,X?,r(21)(p12q22)[83]/45,X?,-21[14]/46,X?,dic r(21;21)(p12q22;q22p12)[3]. CMA has revealed a 5.10 Mb quadruplication at 21q22.12q22.3 and a 2.30 Mb deletion at 21q22.3. CONCLUSION The perinatal phenotype of the two fetuses with ring chromosome 21 mosaicisms is related to the duplication of chromosomal segments near the breakpoints of the chromosomal deletions. The combined chromosomal karyotyping and CMA has enabled prenatal diagnosis and genetic counseling for these families.
Pregnancy ; Female ; Humans ; Mosaicism ; Ring Chromosomes ; Vena Cava, Superior ; Chromosome Aberrations ; Prenatal Diagnosis ; Microarray Analysis ; Fetus/diagnostic imaging*

OBJECTIVE: To investigate the genetic characteristics and cause of death for an infant with alveolar capillary dysplasia and pulmonary vein misalignment (ACD/MPV). METHODS: An infant with ACD/MPV diagnosed at the Affiliated Maternity and Child Health Care Hospital of Nantong University in September 2022 was selected as the study subject. Clinical data of the infant were collected. Whole exome sequencing (WES) was carried out to detect genetic variants in the skin tissue, and Sanger sequencing was performed for verifying the candidate variants in the parents. Droplet digital PCR (ddPCR) was used to determine the mosaicism ratio of the variant in different germ layer-derived samples from the father. RESULTS: The infant had died within 2 days after birth due to hypoxemia and respiratory distress. WES revealed that she has harbored a c.433C>T nonsense variant in exon 1 of the FOXF1 gene, which was unreported previously. Sanger sequencing has verified the variant in the infant, with her mother's locus being the wild-type and a minor variant peak noted in her father. ddPCR indicated that the mosaic ratio of the c.433C>T variant in the father's sperm was 27.18%, with the mosaic ratios of the variant in tissues originating from the three germ layers ranging from 11% to 28%. CONCLUSION The c.433C>T variant derived from the paternal germline and somatic mosaicism of the FOXF1 gene had probably predisposed to the neonatal death of this infant. ddPCR is an effective method for detecting mosaic variants.
Female ; Humans ; Pregnancy ; Child ; Infant ; Infant, Newborn ; Male ; Semen ; Infant Death ; Exons ; Mosaicism ; Forkhead Transcription Factors/genetics*

OBJECTIVE: To delineate the origin and content of a mosaicism small supernumerary marker chromosome (sSMC) in a fetus with combined chromosomal karyotyping, chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH). METHODS: The fetus of a 31-year-old pregnant woman who had presented at the Maternal and Child Health Care Hospital of Longhua District of Shenzhen City in 2022 was selected as the study subject. Non-invasive prenatal testing suggested that the fetus has harbored a 8.75 Mb duplication in 4q12q13.1. With informed consent, amniotic fluid and peripheral blood samples were taken from the couple for chromosomal karyotyping analysis. The origin and content of a sSMC was identified by CMA, and its proportion in amniotic fluid was determined with a FISH assay. RESULTS: The karyotypes of the pregnant woman, her husband and the fetus were respectively determined as 46,XX, 46,XY,inv(9)(p12q12), and 47,XY,inv(9)(p12q12)pat,+mar[75]/ 46,XY,inv(9)(p12q12)pat[25]. CMA test of the amniotic fluid sample was arr[hg19]4p11q13.1(48978053_63145931)×3, which revealed no mosaicism. However, FISH analysis showed that 59% of interphase cells from the cultured amniotic fluid sample had contained three signals for the centromere of chromosome 4, whilst 65% of interphase cells from the re-sampled amniotic fluid had three such signals, which confirmed the existence of trisomy 8 mosaicism. CONCLUSION Chromosomal structural abnormality combined with mosaicism can be delineated with combined chromosomal karyotyping and molecular techniques such as FISH and CMA, which has enabled more accurate counseling for the family.
Humans ; Child ; Female ; Pregnancy ; Adult ; In Situ Hybridization, Fluorescence ; Mosaicism ; Genetic Techniques ; Amniotic Fluid ; Chromosomes, Human, Pair 4

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

OBJECTIVE: To explore the genetic basis for a rare case with Disorder of sex development. METHODS: Clinical data of the patient was collected. Chromosomal karyotyping, SRY gene testing, whole exome sequencing (WES), low-coverage massively parallel copy number variation sequencing (CNV-seq), fluorescence in situ hybridization (FISH), and whole genome sequencing (WGS) were carried out. RESULTS: The patient, a 14-year-old female, had manifested short stature and dysplasia of second sex characteristics. She was found to have a 46,XY karyotype and positive for the SRY gene. No pathogenic variant was found by WES, except a duplication at Yp11.32q12. The result of CNV-seq was 47,XYY. FISH has confirmed mosaicism for a dicentric Y chromosome. A 23.66 Mb duplication on Yp11.32q11.223 and a 5.16 Mb deletion on Yq11.223q11.23 were found by WGS. The breakpoint was mapped at chrY: 23656267. The patient's karyotype was ultimately determined as 46,X,psu idic(Y)(q11.223)/46,X,del(Y)(q11.223). CONCLUSION The combination of multiple methods has facilitated clarification of the genetic etiology in this patient, which has provided a reference for the clinical diagnosis and treatment.
Female ; Humans ; Adolescent ; DNA Copy Number Variations ; In Situ Hybridization, Fluorescence ; Y Chromosome ; Sexual Development ; Mosaicism

OBJECTIVE: To carry out genetic analysis for a fetus with confined placental mosaicism (CPM) for trisomy 2 (T2) in conjunct with fetal uniparental disomy (UPD). METHODS: Amniocentesis and chromosomal karyotyping was carried out for a pregnant woman with a high risk for chromosome 2 anomalies indicated by non-invasive prenatal testing (NIPT). Single nucleotide polymorphism array (SNP-array) and trio-whole exome sequencing (Trio-WES) were carried out. Ultrasonography was used to closely monitor the fetal growth. Multifocal sampling of the placenta was performed after delivery for copy number variation sequencing (CNV-seq). RESULTS: The fetus was found to have a normal chromosomal karyotype. SNP-array has revealed multiple regions with loss of heterozygosity (LOH) on chromosome 2. Trio-WES confirmed the presence of maternal UPD for chromosome 2. Ultrasonography has revealed intrauterine growth restriction and oligohydramnios. Intrauterine fetal demise had occurred at 23⁺⁴ weeks of gestation. Pathological examination had failed to find salient visceral abnormality. The placenta was proved to contain complete T2 by CNV-seq. CONCLUSION T2 CPM can cause false positive result for NIPT and may be complicated with fetal UPD, leading to adverse obstetric outcomes such as intrauterine growth restriction, oligohydramnios and intrauterine fetal demise.
Female ; Humans ; Pregnancy ; Amniocentesis ; Chromosomes, Human, Pair 2/genetics* ; DNA Copy Number Variations ; Fetal Death ; Fetal Growth Retardation/genetics* ; Fetus ; Mosaicism ; Oligohydramnios ; Placenta ; Trisomy/genetics* ; Uniparental Disomy/genetics*