Y-specific sequences in Turner syndrome]

Turner Syndrome (TS) is the only one monosomy that occurrs+ in humans. The cytogenetics of TS is very well known from years. It has been estimated that almost 98-99% of TS foetuses end in abortion. It was suggested that the monosomy arises relatively late during embryonal development and survived TS individuals could be mosaics. It has been proved that mosaic karyotype mos 45,X/46X, + mar(Y) occurrs++ in 2% to 11% of TS patients. The patients having additional cell line containing der(Y) are at increased risk of gonadoblastoma development. In these cases gonadectomy should be considered. Therefore detection of mosaic and establishing the origin of marker chromosome (specially containing Y-specific sequences) is of special importance. The aim of present study was to detect the small mosaics, containing mar(Y) in TS patients, by using PCR and FISH techniques. Eight Y sequences for the PCR analyses as well as bicolor in situ hybridisation with painting probes for Y and X chromosomes have been applied. The positive amplification for Y-specific sequences has been detected in 7% of TS patients. Our results support the thesis that searching for the Y sequences should be introduced to routine genetic TS diagnosis.     

Turner syndrome in a girl with marker chromosome in karyotype]

OBJECTIVES: There are suggestion, that Turner syndrome (TS) patients with mosaic karyotype for a Y-DNA-containing cell line are at risk of Y-induced gonadoblastoma. The TS patients in whom some or all cells contain a marker chromosome of unknown origin and those in whom there is clitoromegaly or other evident virillisation should be tested by FISH or PCR techniques. DESIGN: The aim of our study to present a TS girl with mosaic karyotype and marker chromosome, which origin from X chromosome was detected by FISH method. MATERIAL AND METHODS: 5-years old girl in whom TS was established. Clinical analysis included the full dysmorphic and clinical phenotype of TS. Chromosome analysis was performed on peripheral blood samples using routine cytogenetic methods and FISH technique. RESULTS: Clinical examination of girl showed many typical signs of TS besides of normal weight and length at birth and not typical for TS patients heart defect. First routine chromosome analysis, at age of 6 month, showed only 45,X cell line, Second study revealed mosaic karyotype with marker chromosome. FISH analysis for interphase nuclei and metaphase chromosomes using X centromere probe explained origin of marker from X chromosome. The karyotype was 45,X[155]/46,X,+mar[8].fish mar(X)(DXZ1+). CONCLUSION: Presence of marker chromosome in karyotype of patient with TS may modify their phenotype and it is a indication for molecular examination by FISH technique.     

Turner综合征Y染色体物质嵌合分子遗传学研究

摘要：目的　分析Turner综合征（TS）患儿Y染色体物质及衍生物嵌合发生的情况，为TS患儿诊断后的监测提供科学建议，改善国内TS监测和保健管理的现状。方法　选取2006年2月至2007年8月在重庆医科大学附属儿童医院诊断为TS患儿30例，进行基因组DNA 的Y编码睾丸特异性蛋白基因（TSPY）、 Y染色体中心着丝粒DYZ3重复序列（DYZ3 ）和Y性别决定区域（SRY）3个Y染色体特异序列多聚酶链反应（PCR）检测，反应结果阳性的病例补充SRY探针原位荧光杂交（FISH）分析。结果　基因组DNA 的PCR结果显示，3例患儿的TSPY、 DYZ3扩增均为阳性（10.00%），其中只有1例 SRY 扩增阳性（3.33%）；3例Y染色体物质阳性病例进一步进行FISH研究，结果显示3例SRY杂交信号均为阳性。结论　运用3个Y染色体特异序列的分子遗传学研究，证实Y染色体物质嵌合在TS不少见，每一个TS患儿都应在诊断后进行Y染色体物质的分子遗传学监测。     

Prenatal application of fluorescent in situ hybridization (FISH) for identification of a mosaic Y-chromosome marker, idic(Yp).

An amniocentesis was performed at 13.3 weeks' gestation for advanced maternal age. A mosaic sex chromosome pattern was found: of 50 cells examined, 34 had a 45,X karyotype. In 14 cells with a modal number of 46, a recognizable Y was substituted by a small non-fluorescent marker. C-banding identified the marker as an isodicentric in 12 cells. In two cells, the non-fluorescent marker appeared to be monocentric and looked like a non-fluorescent del (Yq), but could have been an isodicentric Y with inactivation of one of the centromeres. Two cells with a modal number of 47 showed two copies of the monocentric marker. Fluorescent in situ hybridization with an alpha satellite Y-specific centromeric probe confirmed the Y-chromosome origin of the markers and allowed for more accurate prenatal diagnostic information.     

Spontaneous menstruation in patients with Turner syndrome in our observations

OBJECTIVES: Patients with Turner syndrome (TS) may present a wide spectrum of gonadal function including spontaneous menstruation and fertility. DESIGN: The aim of our study was to present the patients with Turner syndrome (TS) with spontaneous menstruations considering specific karyotype and X-inactivation processes. MATERIALS AND METHODS: 5 women from group of 55 patients in age from 15 to 38 years with diagnosis of TS and gonadal function were found. Clinical analysis included the evaluation of spontaneous pubertal development and hormones levels. Cytogenetic analysis was performed on peripheral blood samples using GTG banding technique. X inactivation studies were done by dynamic RBG technique. RESULTS: In two patients with mosaic karyotype and predominant 46,XX line two pregnancies were observed. They had regular menses and normal sexual development. In one patient (karyotype: 45,X[2]/46,XX[98]) spontaneous abortions and premature birth were present. Second patient was (46,XX[245]/46,X,r(X)(p22q26)[5]) in pregnancy in this time. Another three patients menstruated irregularly. The menarche appeared later. The karyotypes were: 46,X,del(X)(p11.3) in two patients and 45,X[64]46,X,r(X) (p22q26)[18]/46,XX[4] in one. CONCLUSIONS: We conclude that spontaneous menstruations and possibility of pregnancy depend on specific karyotype in patients with TS.     

Mucinous cystadenoma in a female patient with 45,X/46,XY karyotype

The mosaic karyotype of 45,X/46,XY has a wide phenotypic spectrum and there are substantial differences between prenatally and postnatally diagnosed cases. The phenotype varies between normal male to classical Turner syndrome. There is a high risk of gonadal tumor development in the dysgenetic gonads of patients with sex chromosome mosaicism. We report a case of a 24-year-old patient with a pelvic mass and amenorrhea referred to our laboratory for karyotyping. Peripheral blood chromosome analysis showed a mosaic karyotype of 45,X[17]/46,XY[83]. The tumor originated from the left ovary and the right ovary was found to be a streak gonad. The uterus was intact. Pathologic examination of the tumor revealed mucinous cystadenoma. Physical examination of the patient showed signs of Turner syndrome, as short stature (145 cm), short neck and asymmetric shoulders. Her mental state was normal. Y chromosome microdeletion screening involving SRY and ZFY genes was performed and no deletion was found. The patient was informed about the condition during the genetic counseling session.     

Scant XYqh- testicular cells with normal SRY was enough to differentiate bilateral testes in a 45,X/46,XYqh- patient

OBJECTIVE: It has been established that in 45,X/46,XY individuals predominance of XY or XO gonadal cells determines gonadal differentiation. However, in some cases there is no concordance between the predominance of XY cells and testis differentiation. Here we describe the SRY findings in a patient bearing a 45,X/46,XYqh- karyotype. STUDY DESIGN: The patient presented two small testes (one with spermatogenesis), a male phenotype, and a predominant 45,X karyotype in leukocytes and gonadal cells. PCRs of SRY, ZFY and Yqh were performed on DNA from leukocytes and from left gonadal tissue. SRY-PCR products were purified and sequenced. RESULTS: A normal SRY sequence was found in both tissues. CONCLUSIONS: Despite the predominance of 45,X cells in gonads, some patients in whom SRY is normal can develop testes, probably due to the presence of alternative mechanisms involved in testicular differentiation; however, further gonadal development could be impaired.     

Reproductive outcomes after preimplantation genetic testing in mosaic Turner syndrome: a retrospective cohort study of 100 cycles

PurposeThe purpose of this study is to explore the reproductive outcomes of women with Turner syndrome (TS) in preimplantation genetic testing (PGT) cycles.MethodsA retrospective study of 100 controlled ovarian stimulating cycles, 68 TS (sixty-four mosaic Turner syndrome (MTS) and four pure Turner syndrome (PTS)) women underwent PGT was conducted from 2013 to 2018.ResultsEmbryo X chromosome abnormal rates of TS women were significantly higher than women with normal karyotype (7.04 vs 1.61%, P<0.01). Cumulative live birth rates (CLBR) after PGT-NGS treatment were lower in TS than control (31.15 vs 45.59%, P<0.05). Clinical pregnancy rates per transfer (CPR), miscarriage rates (MR) and live birth rates per transfer (LBR) remained comparable between TS and control group. Reproductive outcomes (X chromosome abnormal rates, CPR, MR, LBR and CLBR) among low (<10%), medium (10–50%) and high (>50%) level 45,X mosaicism groups were not statistically different.ConclusionsTo avoid high risk of embryo X chromosome abnormalities, prenatal or preimplantation genetic testing should be recommended to mosaic or pure TS patients.     

Polycystic Ovary Syndrome and Incidental Diagnosis of Mosaic Turner Syndrome

BackgroundPolycystic ovary syndrome (PCOS) is a common condition in women of reproductive age. Mosaic Turner syndrome (TS) is a genetic disorder with significant phenotypic variability. The occurrence of PCOS in women with mosaic TS has been infrequently studied.CaseA 30-year-old nulligravid woman presented with oligomenorrhea, hyperandrogenism, infertility, and ultrasound polycystic ovary morphology. She was diagnosed with PCOS and conceived following ovulation induction. After 2 inconclusive non-invasive prenatal screening results, she was referred to medical genetics. A maternal karyotype resulted in a diagnosis of 45,X/46,XX mosaic TS. She delivered a healthy 46,XY infant at term.ConclusionPCOS can affect women with mosaic TS. Further studies are needed to better characterize the reproductive profile of women with mosaic TS, including the presentation of concurrent PCOS.     

Spontaneous Sexual Development and Heavy Menstrual Bleeding in 45,X Monosomy and 45,X/47,XXX Mosaic Turner Syndrome and a Review of the Literature

Turner syndrome (TS) is one of the most common sex chromosome disorders and is characterized by short stature and gonadal dysgenesis. A few patients with TS achieve normal sexual development, menarche, and even pregnancy. We encountered two cases of Turner syndrome with spontaneous sexual development and menstruation. The patients had different karyotypes, 45,X monosomy and 45,X/47,XXX mosaic TS, and presented with severe anemia due to excessive menstrual bleeding. Abnormal uterine bleeding patterns are expected in patients with primary ovarian insufficiency; however, the menstrual patterns of patients with TS have not been well described in the literature. Here, we describe these cases along with a brief review of the relevant literature.     

Globozoospermia: Do Y-chromosome microdeletions play a role in this rare spermatogenic disorder?

OBJECTIVE: To explore the possible relationship between Y-chromosome microdeletions and a rare spermatogenic disorder, globozoospermia. STUDY DESIGN: Twelve patients with 100% globozoospermia were evaluated. Each man was questioned about his medical and surgical history and underwent a thorough andrologic examination. Plasma follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and prolactin levels were measured. Routine sperm analysis and morphology with electron microscopy were done. A set of 17 Y-specific sequence-tagged sites spanning the 3 AZF regions and also RBM1, ZFY, SRY, sY78, CDY, BPY2 and PRY were tested to detect the existence of Y-chromosome microdeletions by polymerase chain reaction. RESULTS: The mean age of the patients was 36 years (range, 27-42). No patient had abnormal blood concentrations of FSH, LH, testosterone or prolactin. Semen analysis revealed normal values for volume (2.2 mL) and concentration (32 x 10(6)/mL) but subnormal values for motility (37%) and progressive motility (24%). On light and electron microscopy, all the spermatozoa were round headed, with abnormal morphologic features. Patients had normal 46,XY karyotyping. No microdeletion of the Y chromosome was detected in any patient. CONCLUSION: Although this study did not find any Y-chromosome microdeletions in patients with globozoospermia, the exact genetic locus resulting in this pathology requires further study.     

The vanishing twin: an explanation for discordance between chorionic villus karyotype and fetal phenotype.

One 'erroneous' diagnosis occurred in 200 first-trimester chorionic villus samples (CVS) analysed. In direct preparations following 24 h incubation as well as in long-term cultures, a 46,XX karyotype was observed in the villi (28 and 25 cells, respectively). At 20 weeks of gestation, labour was induced because of fetal death in utero. An autopsy performed on the fetus revealed a male phenotype. Placenta and fetal tissues were not submitted for cytogenetic studies. The discordant CVS karyotype (46,XX), in view of the male fetal phenotype, prompted further cytogenetic and molecular studies. Chromosome marker studies on the parents' blood and chorionic villi confirmed both maternal and paternal inheritance of chromosomes in the CVS. DNA studies on formalin-fixed skin using a Y-specific probe, DYZ1, confirmed the presence of a Y chromosome in the fetus. The most likely cause of the discrepant CVS karyotype is the presence of an undetected degenerating dizygotic twin.     

1例嵌合型45,X/46,X,r(Y)患者的遗传学分析

目的:应用细胞遗传学和分子生物学技术分析1例嵌合型45,X/46,X,r(Y)患者的核型。方法:应用常规染色体标本制备方法进行G-显带和C-显带;并应用CEPX(DXZ1,Xp11.1-q11.1,Spectrum Green,Vysis)探针、LSI SRY(Yp11.3,Spectrum Orange,Vysis)探针和CEP18(D18Z1,18p11.1-q11.1,Spectrum Aqua,Vysis)与患者的中期分裂相进行荧光原位杂交(fluorescence in situ hybridization,FISH);同时应用PCR技术对患者进行Y染色体微缺失检测。结果:结合G-显带、C-显带、FISH检测结果和Y染色体微缺失的检测结果,确定该患者核型为46,X,r(Y)(p11.3q12)[85]/45,X[15]。Yq11区生精基因微缺失检测未显示该患者存在缺失。结论:细胞遗传学检测结合FISH可以诊断复杂的染色体异常,为患者提供正确的遗传咨询和生育指导。     

An infertile 45,X male with a SRY-bearing chromosome 13: a clinical case report and literature review

PurposePatients with a karyotype of 45,X (monosomy X) normally display a female phenotype. However, in some rare cases, monosomy X is associated with maleness. Here we describe a case of a male with a 45,X karyotype and primary infertility, which prompted molecular investigation of the sex-determination gene SRY.MethodsKaryotyping was performed by GTG-banded chromosome analysis. The presence and location of SRY was investigated using PCR and FISH, respectively.ResultsPCR confirmed the presence of the SRY gene while FISH analysis demonstrated its location on the p arm of chromosome 13. These findings demonstrate that autosomal retention of SRY can be sub-microscopic and emphasize the importance of PCR and FISH in the genetic workup of the monosomic X male.     

Screening of seven putative 45,X subjects with deoxyribonucleic acid probes to detect low-level mosaicism for Y cell lines

The frequency of monosomy X in cytogenetically abnormal abortion material (10% to 15%) suggests that viable 45,X subjects might have covert mosaicism for X or Y cell lines. The deoxyribonucleic acid samples from seven 45,X subjects with Turner syndrome were examined with three Y-specific deoxyribonucleic acid probes. Successive hybridizations with each of these three sensitive deoxyribonucleic acid probes did not reveal any Y-specific band.     

The Turner syndrome in patient with 45X/47XXX mosaic karyotype – case report

Abstract

Background: Turner syndrome (TS) is a gonadal dysgenesis related to partial or total lack of one of the X chromosomes. It this report we describe a young patient presenting some somatic features of TS, who underwent spontaneous puberty and was eumenoorheic up to the age of 23.

Methods: Using fluorescent in situ hybridization (FISH) mosaic karyotype (45X[131]/47XXX[9]) of TS and triple X syndrome was found.

Results: She presented uncommon for TS somatic hemihypotrophy and underwent growth hormone and surgical therapy. The patient was diagnosed with premature ovarian failure when she was 23, with absent follicular reserve. Clinical features of this case and a few published cases will be reviewed briefly.     

Fetal cells in the maternal circulation: detection of Y-sequence by gene amplification.

Detection of a Y-specific sequence in the maternal circulation has clinical importance because it would be useful in determining fetal gender in mothers with severe X-linked disorders. The method described in this paper has the advantage of requiring only small amounts of maternal blood. Numerous attempts have been made to identify XY cells in the blood of mothers bearing male fetuses; however, the results have been controversial. In this study, a member of the DYZ1 family and the XY homologous region of the amelogenin gene were used as targets for polymerase chain reaction detection of the Y chromosome. The subjects in this study were a group of 100 pregnant women at 17-20 weeks' gestation and 30 puerperal women who had given birth 2-5 days previously. All of the former underwent amniocentesis, with venous blood samples drawn before the procedure. Forty-five fetuses were confirmed as male by karyotyping amniocytes, and 30 of these were positive for the Y sequence in the DYZ1 region (sensitivity 66.7%). However, ten of the 55 cases diagnosed as female were also positive, giving a specificity of only 81.8%. Thus, the positive and negative predictive values were each 75%. In the amelogenin gene study, a positive Y signal was not detected in any of the cases examined. This study demonstrates the usefulness of polymerase chain reaction detection of Y-specific sequences in the maternal circulation. However, further investigation is necessary to increase the reliability for clinical application, because the method does produce false-positive results.     

Progressive increase of the mosaic level for 45,X in 45,X/46, XX at different amniocenteses and postnatal progressive decrease of the 45,X cell line in a mosaic 45,X/46, XX fetus with a favorable outcome

ObjectiveWe present progressive increase of the mosaic level for 45,X in 45,X/46, XX at different amniocenteses and postnatal progressive decrease of the 45,X cell line in a mosaic 45,X/46, XX fetus with a favorable outcome.Case reportA 35-year-old, primigravid woman underwent amniocentesis at 16 weeks of gestation because of the advanced maternal age. Amniocentesis revealed a karyotype of 45,X [6]/46,XX [14]. Among 20 colonies of cultured amniocytes, six colonies had a karyotype of 45,X, whereas the other 14 colonies had a karyotype of 46,XX. Simultaneous array comparative genomic hybridization (aCGH) on uncultured amniocytes revealed the result of arr [GRCh37] (X) × 1 [0.42] (1–22) × 2. Prenatal ultrasound findings were unremarkable. Repeat amniocentesis at 33 weeks of gestation revealed a karyotype of 45,X [13]/46,XX [7]. Among 20 colonies of cultured amniocytes, 13 colonies had a karyotype of 45,X, whereas the other seven colonies had a karyotype of 46,XX. Simultaneous interphase fluorescence in situ hybridization (FISH) analysis on 100 uncultured amniocytes revealed that 44 cells had monosomy X consistent with 44% mosaicism for 45,X, whereas the rest cells had disomy X. At 38 weeks of gestation, a 2675-g phenotypically normal female baby was delivered. The karyotypes of cord blood, umbilical cord and placenta were 45,X [12]/46,XX [28], 45,X [12]/46,XX [28] and 46,XX [40/40], respectively. When follow-up at age three months, the neonate was normal in development. The karyotypes of peripheral blood was 45,X [4]/46,XX [36], and interphase FISH analysis on 100 buccal mucosal cells showed monosomy X in 11 cells consistent with 11% mosaicism for 45,X, whereas the rest cells had disomy X.ConclusionProgressive increase of the mosaic level for 45,X in 45,X/46, XX at different amniocenteses can be associated with a favorable outcome and postnatal progressive decrease of the 45,X cell line.     

Ring X and other structural X chromosome abnormalities: X inactivation and phenotype

Patients who carry a structural abnormality of the X chromosome are a fascinating group who have provided opportunities to evaluate genotype/phenotype correlation in relation to X chromosome content and inactivation. Turner syndrome (TS) is most commonly associated with a 45,X karyotype and presents with an array of phenotypes, the main ones being poor viability in utero, ovarian failure and infertility, short stature, lymphedema, and other congenital malformations but usually not mental retardation. In some TS patients the karyotype shows both a normal X and a structurally rearranged X chromosome. These structural abnormalities, which include deletions, duplications, inversions, translocations, and rings, are associated with chromosome breaks and significant imbalance of gene content of the X chromosome. However, such abnormalities are generally well tolerated because of the preferential inactivation of the abnormal X, which can restore, at least in part, a balanced genetic makeup. This beneficial effect of X inactivation results in a mild phenotype in most patients with structural abnormalities of the X, similar to that found in TS patients with a 45,X karyotype. However, in cases of ring X chromosomes and of X/autosome translocations the incidence of mental retardation and other congenital abnormalities can be significantly higher than in TS. These abnormal phenotypes can be ascribed to failed or partial X inactivation and/or incomplete selection in favor of cells with normal balance of gene expression. In this article, we present phenotype/genotype correlation in female patients with structural abnormalities of the X and address the role of X inactivation and cell selection in the phenotypic findings. Our review emphasizes a subset of rare patients with ring X chromosomes who have provided evidence of a direct role for X inactivation in determining phenotypes.