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.

Pregnancy ; Female ; Humans ; Mosaicism ; Prenatal Diagnosis ; Prenatal Care ; Aneuploidy

OBJECTIVE: To explore the coincidence rate of G-banding karyotype analysis and fluorescence in situ hybridization (FISH) for the diagnosis of children with sex chromosome mosaicisms. METHODS: A retrospective analysis was carried out for 157 children with suspected sex chromosome abnormalities who had presented at Shenzhen Children's Hospital from April 2021 to May 2022. Interphase sex chromosome FISH and G-banding karyotyping results were collected. The coincidence rate of the two methods in children with sex chromosome mosaicisms was compared. RESULTS: The detection rates of G-banding karyotype analysis and FISH were 26.1% (41/157) and 22.9% (36/157) , respectively (P > 0.05). The results of G-banding karyotype analysis showed that 141 cases (89.8%) were in the sex chromosome homogeneity group, of which only 5 cases (3.5%) were inconsistent with the results of FISH. There were 16 cases (10.2%) in the sex chromosome mosaicism group, of which 11 cases (68.8%) were inconsistent with the results of FISH. There was a statistical difference between the two groups in the coincidence rate of the results of the two methods (P < 0.05). CONCLUSION No significant difference was found between G-banding karyotype analysis and FISH in the detection rate of chromosome abnormalities. The coincidence rate in the mosaicism group was lower than that in the homogeneity group, and the difference was statistically significant. The two methods should be combined for clinical diagnosis.
Humans ; Mosaicism ; In Situ Hybridization, Fluorescence/methods* ; Retrospective Studies ; Karyotyping ; Chromosome Aberrations ; Sex Chromosome Aberrations ; Karyotype ; Chromosome Banding ; Sex Chromosomes

OBJECTIVE: To explore the genetic basis, clinical phenotype and pathogenesis for a child with mosaicism ring chromosome 4. METHODS: Clinical data of the child was collected. Peripheral blood chromosomal karyotype G banding analysis, chromosomal microarray analysis (CMA), fluorescence in situ hybridization (FISH) were carried out for the child, in addition with a review of the literature. RESULTS: The child was born full-term with low birth weight, facial dysmorphism, patent ductus arteriosus and ventricular septal defect. His karyotype was determined as mos46,XY,r(4)(p16.3q35.2)[259]/45,XY,-4[25]/47,XY,r(4)(p16.3q35.2), +r(4)(p16.3q35.2)[8]/46,XY,der(4)del(4)(p16.3)inv(4)(p16.3q31.1)[6]/46,XY,dic?r(4;4)(p16.3q35.2;p16.3q35.2)[4]/48,XY,r(4)(p16.3q35.2),+r(4)(p16.3q35.2)×2[3]/46,XY,r(4)(p1?q2?)[2]; CMA result was arr[GRCH37]4p16.3(68 345-2 981 614)×1; FISH result was 45,XY,-4[12]/45,XY,-4×2,+mar1.ish r1(4)(WHS-,D4Z1+)[1]/ 46,XY,-4,+mar1.ishr1(4)(WHS-,D4Z1+)[73]/46,XY,-4,+mar2.ishr2(4)(WHS-,D4Z1++)[1]/47,XY,-4,+mar1×2.ishr1(4) (WHS-, D4Z1+)×2[4]/46,XY,del(4)(p16.3).ish del(4)(p16.3)(WHS-,D4Z1+)[9]. CONCLUSION In this case, the ring chromosome 4 as a de novo variant has produced a number of cell lines during embryonic development and given rise to mosaicism. The clinical phenotype of ring chromosome 4 is variable. The instability of the ring chromosome itself, presence of mosaicism, chromosome breakpoint and range of deletion and/or duplication may all affect the ultimate phenotype.
Humans ; Pregnancy ; Female ; Ring Chromosomes ; In Situ Hybridization, Fluorescence ; Karyotyping ; Karyotype ; Mosaicism

Turner syndrome is a congenital condition affecting 1 in every 2500 female live births. This condition is characterized by complete or partial loss of the X chromosome. They commonly present with normal female external and internal genitalia and may develop hypogonadism and streak ovaries later in life. We describe an unusual presentation of a case of Turner syndrome – a 31-year-old Filipino with male phenotype mosaic Turner syndrome, with 46,X,+mar[46]/45,X[4] chromosome, presenting with ambiguous genitalia and a pelvoabdominal mass. The patient underwent exploratory laparotomy, peritoneal fluid cytology, adhesiolysis, tumor debulking (gonadectomy) appendectomy, omentectomy, identification and inspection of bilateral ureters and bladder, gonioscopy and biopsy of the urogenital cavity (bladder vs. vagina). Histopathology revealed a mixed gonadal tumor, consisting of 70% yolk sac tumor, and 30% dysgerminoma. The patient eventually succumbed to postoperative complications. Postmortem fluorescence-in situ hybridization revealed a 46,X,+mar[46]/45,X,[4].ish der (Y) (DYZ3+), a marker of chromosome Y origin, consistent with a mosaic type Turner syndrome, associated with increased risk for gonadal malignancy.
Dysgerminoma ; mixed germ cell tumor ; mosaicism ; yolk sac tumor

Mosaic chromosomal alteration (mCA) is referred to as large-scale somatic mutations on chromosomes, which results in diverse karyotypes in body. The mCA is regarded as one of the phenotypes of aging. Studies have revealed its associations with many chronic diseases such as hematopoietic cancers and cardiovascular diseases, but its genetic basis (e.g. genetic susceptibility variants) is still under-investigated. This paper reviews GWAS studies for mCA on autosomal chromosomes and sex chromosomes [mosaic loss of the Y chromosome (mLOY) and mosaic loss of the X chromosome (mLOX)] based on large population, respectively. Most of the genetic susceptibility loci found in studies for autosomal mCA were associated with copy-neutral loss of heterozygosity. The study of sex chromosome mCA focused on mosaic loss mutations. The number of genetic susceptibility loci for mLOY was high (up to 156), but it was relatively less for mLOX.
Humans ; Male ; Genome-Wide Association Study/methods* ; Mosaicism ; Genetic Predisposition to Disease ; Chromosomes, Human, Y ; Mutation

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*