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Yang Y, Hao W. Molecular and cytogenetic analysis of small supernumerary marker chromosomes in prenatal diagnosis. Mol Cytogenet 2023; 16:23. [PMID: 37667392 PMCID: PMC10476427 DOI: 10.1186/s13039-023-00655-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 08/23/2023] [Indexed: 09/06/2023] Open
Abstract
BACKGROUND Small supernumerary marker chromosome (sSMC) is a structurally abnormal chromosome of unknown origin by conventional cytogenetics. The understanding of clinical significance of sSMC is still limited in prenatal diagnosis. The presence of sSMC poses a challenge for genetic counselling. METHODS We obtained the clinical information of 25 cases with sSMC. The fetal samples were subjected to multiple molecular and cytogenetic approaches including karyotype analysis, chromosomal microarray analysis, bacterial artificial chromosomes-on-beads assay, and fluorescence in situ hybridization. RESULTS Seven sSMCs were found to be r(X), and five of the cases terminated the pregnancy. Three markers were idic(15), and one of the cases was normal at birth. Two markers were i(12p), and both cases terminated the pregnancy. Other markers were r(Y) (outcome: normal at birth), i(18p) (outcome: stillbirth), der(15) (outcome: terminated), del(9) (outcome: terminated), dup(13) (outcome: follow-up loss), and derived from chromosome 21 (outcome: stillbirth). Seven markers were of unknown origin because not all methods were applied to them. CONCLUSION Applying multiple molecular and cytogenetic approaches could identify the origin and genetic content of sSMC to assist the genetic counselling in prenatal diagnosis.
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Affiliation(s)
- Yang Yang
- Prenatal Diagnosis Center, Hangzhou Maternity and Child Care Hospital, #369 Kunpeng Road, Shangcheng District, Hangzhou, 310008, Zhejiang, China
| | - Wang Hao
- Prenatal Diagnosis Center, Hangzhou Maternity and Child Care Hospital, #369 Kunpeng Road, Shangcheng District, Hangzhou, 310008, Zhejiang, China.
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
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Aksoy E, Cogulu O, Pariltay E, Ozen S, Ata A, Karaca E, Darcan S. Association between clinical variations and copy number variations in cases with Turner syndrome. J Pediatr Endocrinol Metab 2022; 35:1161-1168. [PMID: 35953302 DOI: 10.1515/jpem-2022-0153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 07/14/2022] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Turner syndrome (TS) is one of the most common chromosomal abnormalities with an incidence of approximately one in 2,500 live births. Short stature and primary ovarian insufficiency are two most important characteristic findings of TS. Turner syndrome karyotypes include monosomy X, mosaic structure and X chromosome structural anomalies. Genotypic and phenotypic characteristics vary among cases. This study aimed to evaluate the clinical variations observed in TS cases with the copy number variations (CNV) detected by microarray study. METHODS Fifty-three patients diagnosed with TS, between the ages of 0-18 were included in the study. Peripheral blood samples were taken from 36 cases for microarray study. RESULTS Karyotypes were as follows: thirty-three of cases were 45,X, 7 were 45,X/46,XX, 6 were 45,X/46,Xi(Xq), 2 were 46,Xi(Xq), 2 were 45,X/46,r(X), 1 was 45,X/46,Xi(Xp), 1 was 45,X/46,XY and 1 was 45,X/46,X+mar(idicY) karyotype. A significant correlation was found between karyotype groups and FSH values of the cases (p=0.034). In monosomy X and mosaic isochromosome Xq cases, the FSH value was found to be significantly higher than those with 45,X/46,XX mosaic karyotype. CNVs were found in 8 (22.2%) out of 36 cases whose microarray study was performed. Unexpected atypical findings were discussed in the light of the characteristics of CNVs. CONCLUSIONS In conclusion, the microarray method has a great contribution in explaining many unexpected findings in TS cases. Moreover, those CNV findings may contribute for the explanation of the underlying mechanisms of those anomalies.
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Affiliation(s)
- Ezgi Aksoy
- Department of Child Health and Diseases, Faculty of Medicine, Ege University, Izmir, Turkey
| | - Ozgur Cogulu
- Department of Medical Genetics, Faculty of Medicine, Ege University, Izmir, Turkey
| | - Erhan Pariltay
- Department of Medical Genetics, Faculty of Medicine, Ege University, Izmir, Turkey
| | - Samim Ozen
- Department of Pediatric Endocrinology and Diabetes, Faculty of Medicine, Ege University, Izmir, Turkey
| | - Aysun Ata
- Department of Pediatric Endocrinology and Diabetes, Faculty of Medicine, Ege University, Izmir, Turkey
| | - Emin Karaca
- Department of Medical Genetics, Faculty of Medicine, Ege University, Izmir, Turkey
| | - Sukran Darcan
- Department of Pediatric Endocrinology and Diabetes, Faculty of Medicine, Ege University, Izmir, Turkey
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Ghosh S, Roy S, Halder A. Study of frequency and types of chromosomal abnormalities in phenotypically female patients with amenorrhea in Eastern Indian population. J Obstet Gynaecol Res 2020; 46:1627-1638. [PMID: 32515109 DOI: 10.1111/jog.14318] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 02/04/2020] [Accepted: 05/07/2020] [Indexed: 01/15/2023]
Abstract
AIM This comprehensive review article aims to comprehend the frequency and prevalence of chromosomal abnormalities in both primary amenorrhea (PA) and secondary amenorrhea (SA) cases and correlating it with their phenotypes, clinical features and hormonal profiles. METHODS Research publications on prevalence of chromosomal abnormalities in both PA and SA cases worldwide and its etiology, clinical features, hormonal profiles; their correlation with chromosomal profiles were searched for on the internet, including general search engines and respective scientific sites. Only published, relevant and authentic data conducted on phenotypically female patients were considered. Another aspect of amenorrhea occurs due to several clinical conditions apart from cytogenetic viewpoint were not considered or discussed in detail. RESULTS As literature study suggests; considering various etiology of amenorrhea counting anatomic defect of the hypothalamus or genetic defect, and various acquired causes of chromosomal anomalies contribute to be one of the major etiologies of both PA and SA; ranging from 15.9% to 63.3% in case of PA and from 3.9% to 44.4% in case of SA. In spite of the presence of any other factors responsible condition, the genetic factors need to be emphasized, which might include single gene disorders or chromosomal disorders. Individuals with chromosomal anomalies reported a wide range of abnormalities in phenotypes, as well as in other clinical features and hormonal profiles. CONCLUSION This comprehensive review is the first structured review article that encompasses the cytogenetic profile of the amenorrhea cases and correlating it with their phenotypes, clinical features and hormonal profiles from Eastern India.
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Affiliation(s)
- Shanoli Ghosh
- Department of Genetics, Vivekananda Institute of Medical Sciences, Kolkata, India
| | - Sanchita Roy
- Department of Anatomy, Diamond Harbour Government Medical College and Hospita, Diamond Harbour, India
| | - Ajanta Halder
- Department of Genetics, Vivekananda Institute of Medical Sciences, Kolkata, India
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Abstract
Turner syndrome is one of the most common sex chromosomal anomalies, characterized by the complete or partial loss of one X chromosome. Females with Turner syndrome are characterized by skeletal abnormalities, short stature and primary ovarian insufficiency. The aim of this narrative review was to identify the underlying mechanisms of osteoporosis in Turner syndrome, summarize its clinical manifestations and provide suggestions regarding the management of osteoporosis. Girls and women with Turner syndrome have lower bone mineral density and a higher fracture rate than healthy individuals. The most important risk factors for osteoporosis are inadequately treated primary ovarian insufficiency, followed by intrinsic bone abnormalities. Comorbidities that further increase the risk of osteoporosis include vitamin D deficiency, celiac disease and inflammatory bowel disease. In addition, hearing problems can predispose to falls. Early initiation of hormone replacement therapy (HRT) at the age of 11-13 years, prompt titration to the adult dose after 2 years and long-term follow-up to ensure compliance with HRT are the cornerstones of osteoporosis prevention in women with Turner syndrome.
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Chauhan P, Jaiswal SK, Lakhotia AR, Rai AK. Molecular cytogenetic characterization of two Turner syndrome patients with mosaic ring X chromosome. J Assist Reprod Genet 2016; 33:1161-8. [PMID: 27387888 DOI: 10.1007/s10815-016-0761-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 06/20/2016] [Indexed: 01/15/2023] Open
Abstract
PURPOSE In the present study, we reported two cases of TS with mosaic ring X chromosome showing common clinical characteristics of TS like growth retardation and ovarian dysfunction. The purpose of the present study was to cytogenetically characterize both cases. METHODS Whole blood culture and G-banding were performed for karyotyping the cases following standard protocol. Origin of the ring chromosome and degree of mosaicism were further determined by fluorescence in situ hybridization (FISH). Breakpoints and loss of genetic material in formation of different ring X chromosomes r (X) in cases were determined with the help of cytogenetic microarray. RESULTS Cases 1 and 2 with ring chromosome were cytogenetically characterized as 45, X [114]/46Xr (X) (p22.11q21.32) [116] and 45, X [170]/46, Xr (X) (p22.2q21.33) [92], respectively. Sizes of these ring X chromosomes were found to be ~75 and ~95 Mb in cases 1 and 2, respectively, using visual estimation as part of cytogenetic observation. In both cases, we observed breakpoints on Xq chromosome were within relatively narrow region between Xq21.33 and Xq22.1 compared to regions in previously reported cases associated with ovarian dysgenesis. CONCLUSIONS Our observation agrees with the fact that despite of large heterogeneity, severity of the cases with intact X-inactive specific transcript (XIST) is dependent on degree of mosaicism and extent of Xq deletion having crucial genes involved directly or indirectly in various physiological involving ovarian cyclicity.
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Affiliation(s)
- Pooja Chauhan
- Centre for Genetic Disorders, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Sushil Kumar Jaiswal
- Centre for Genetic Disorders, Institute of Science, Banaras Hindu University, Varanasi, India
| | | | - Amit Kumar Rai
- Centre for Genetic Disorders, Institute of Science, Banaras Hindu University, Varanasi, India.
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Kalkan R, Özdağ N, Bundak R, Çirakoğlu A, Serakinci N. A unique mosaic Turner syndrome patient with androgen receptor gene derived marker chromosome. Syst Biol Reprod Med 2016; 62:77-83. [PMID: 26744914 DOI: 10.3109/19396368.2015.1109007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Patients with Turner syndrome are generally characterized by having short stature with no secondary sexual characteristics. Some abnormalities, such as webbed neck, renal malformations (>50%) and cardiac defects (10%) are less common. The intelligence of these patients is considered normal. Non-mosaic monosomy X is observed in approximately 45% of postnatal patients with Turner syndrome and the rest of the patients have structural abnormalities or mosaicism involving 46,X,i(Xq), 45,X/46,XX, 45,X and other variants. The phenotype of 45,X/46,X,+mar individuals varies by the genetic continent and degree of the mosaicism. The gene content of the marker chromosome is the most important when correlating the phenotype with the genotype. Here we present an 11-year-old female who was referred for evaluation of her short stature and learning disabilities. Conventional cytogenetic investigation showed a mosaic 45,X/46,X,+mar karyotype. Fluorescence in situ hybridization showed that the marker chromosome originated from the X chromosome within the androgen receptor (AR) and X-inactive specific transcript (XIST) genes. Therefore, it is possible that aberrant activation of the marker chromosome, compromising the AR and XIST genes, may modify the Turner syndrome phenotype.
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Affiliation(s)
| | | | - Rüveyde Bundak
- b Department of Pediatrics , Faculty of Medicine, Near East University , Nicosia , Turkish Republic of Northern Cyprus
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Eckhauser A, South ST, Meyers L, Bleyl SB, Botto LD. Turner Syndrome in Girls Presenting with Coarctation of the Aorta. J Pediatr 2015; 167:1062-6. [PMID: 26323199 DOI: 10.1016/j.jpeds.2015.08.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 07/06/2015] [Accepted: 08/03/2015] [Indexed: 12/20/2022]
Abstract
OBJECTIVE To evaluate the frequency of Turner syndrome in a population-based, statewide cohort of girls with coarctation of the aorta. STUDY DESIGN The Utah Birth Defects Network was used to ascertain a cohort of girls between 1997 and 2011 with coarctation of the aorta. Livebirths with isolated coarctation of the aorta or transverse arch hypoplasia were included and patients with complex congenital heart disease not usually seen in Turner syndrome were excluded. RESULTS Of 244 girls with coarctation of the aorta, 77 patients were excluded, leaving a cohort of 167 girls; 86 patients (51%) had chromosomal studies and 21 (12.6%) were diagnosed with Turner syndrome. All patients were diagnosed within the first 4 months of life and 5 (24%) were diagnosed prenatally. Fifteen patients (71%) had Turner syndrome-related findings in addition to coarctation of the aorta. Girls with mosaicism were less likely to have Turner syndrome-associated findings (3/6 mosaic girls compared with 12/17 girls with non-mosaic 45,X). Twelve girls (57%) diagnosed with Turner syndrome also had a bicommissural aortic valve. CONCLUSION At least 12.6% of girls born with coarctation of the aorta have karyotype-confirmed Turner syndrome. Such a high frequency, combined with the clinical benefits of an early diagnosis, supports genetic screening for Turner syndrome in girls presenting with coarctation of the aorta.
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Affiliation(s)
- Aaron Eckhauser
- Section of Pediatric Cardiothoracic Surgery, Department of Surgery, University of Utah, Salt Lake City, UT; Heart Center at Primary Children's Hospital, Intermountain Healthcare, Salt Lake City, UT.
| | - Sarah T South
- Department of Pathology, University of Utah, Salt Lake City, UT
| | - Lindsay Meyers
- Heart Center at Primary Children's Hospital, Intermountain Healthcare, Salt Lake City, UT; Division of Pediatric Cardiology, Department of Pediatrics, University of Utah, Salt Lake City, UT
| | - Steven B Bleyl
- Division of Pediatric Cardiology, Department of Pediatrics, University of Utah, Salt Lake City, UT
| | - Lorenzo D Botto
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, UT
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9
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Pietzner V, Weigel JFW, Wand D, Merkenschlager A, Bernhard MK. Low-level hyperinsulinism with hypoglycemic spells in an infant with mosaic Turner syndrome and mild Kabuki-like phenotype: a case report and review of the literature. J Pediatr Endocrinol Metab 2014; 27:165-70. [PMID: 23950569 DOI: 10.1515/jpem-2013-0090] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 07/22/2013] [Indexed: 11/15/2022]
Abstract
BACKGROUND Impaired glucose tolerance and type 2 diabetes are well-known features in patients with Turner syndrome. To the best of our knowledge, there is only one reported case of hyperinsulinemic hypoglycemia associated with a complex mosaic Turner syndrome available in the current literature. PATIENT We report on the case of a 13-month-old girl with a complex mosaic Turner genotype and mild hyperinsulinemic hypoglycemia responsive to diazoxide therapy. RESULTS Cytogenetic analyses showed two or possibly three cell lines. Sixty percent of the cell lines had a 45,X genotype and the rest had 46,XX with a marker ring chromosome. Diagnosis of a mosaic Turner syndrome and mild Kabuki-like phenotype was confirmed. CONCLUSIONS Despite the rareness of this case, clinicians should be aware of the possibility of hyperinsulinemic hypoglycemia in patients with Turner syndrome to prevent further brain damage caused by hypoglycemic episodes and seizures. Although the mechanism leading to hyperinsulinism in this condition is still unknown, the present report discusses this rare presentation and gives an overview on the current literature regarding this case.
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Chacko E, Graber E, Regelmann MO, Wallach E, Costin G, Rapaport R. Update on Turner and Noonan syndromes. Endocrinol Metab Clin North Am 2012; 41:713-34. [PMID: 23099266 DOI: 10.1016/j.ecl.2012.08.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Turner syndrome (TS) and Noonan syndrome (NS) have short stature as a constant feature; however, both conditions can present clinicians with a challenging array of genetic, cardiovascular, developmental, and psychosocial issues. In recent years, important advances have been achieved in each of these areas. This article reviews these two syndromes and provides updates on recent developments in diagnostic evaluation, growth and development, psychological issues, and treatment options for patients with TS and NS.
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Affiliation(s)
- Elizabeth Chacko
- Division of Pediatric Endocrinology and Diabetes, Mount Sinai School of Medicine, New York, NY 10029, USA
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Rao Kandukuri L, Padmalatha V, Kanakavalli M, Turlapati R, Swapna M, Vidyadhari M, Saranaya G, Himaja K, Deenadayal M, Kumar Sethi B, Deb P, Gupta N, Chakraborthy B, Nallari P, Singh L. Unique case reports associated with ovarian failure: necessity of two intact x chromosomes. Case Rep Genet 2012; 2012:640563. [PMID: 23074690 PMCID: PMC3447217 DOI: 10.1155/2012/640563] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Accepted: 02/07/2012] [Indexed: 11/18/2022] Open
Abstract
Premature ovarian failure is defined as the loss of functional follicles below the age of 40 years and the incidence of this abnormality is 0.1% among the 30-40 years age group. Unexplained POF is clinically recognized as amenorrhoea (>6 months) with low level of oestrogen and raised level of Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH > 20 IU/l) occurring before the age of 40. It has been studied earlier that chromosomal defects can impair ovarian development and its function. Since there is paucity of data on chromosomal defects in Indian women, an attempt is made to carry out cytogenetic evaluation in patients with ovarian failure. Cytogenetic analysis of women with ovarian defects revealed the chromosome abnormalities to be associated with 14% of the cases analyzed. Interestingly, majority of the abnormalities involved the X-chromosome and we report two unique abnormalities, (46,XXdel(Xq21-22) and q28) and (mos,45XO/46,X+ringX) involving X chromosome in association with ovarian failure. This study revealed novel X chromosome abnormalities associated with ovarian defects and these observations would be helpful in genetic counseling and apart from, infertility clinics using the information to decide suitable strategies to help such patients.
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Affiliation(s)
- Lakshmi Rao Kandukuri
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
- Genome Foundation, Centre for Cellular and Molecular Biology, Hyderabad 500007, India
| | - Venkata Padmalatha
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
| | - Murthy Kanakavalli
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
| | - Raseswari Turlapati
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
| | - Mangalipally Swapna
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
- Genome Foundation, Centre for Cellular and Molecular Biology, Hyderabad 500007, India
| | - Metuku Vidyadhari
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
- Genome Foundation, Centre for Cellular and Molecular Biology, Hyderabad 500007, India
| | - Govindaraghavan Saranaya
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
- Genome Foundation, Centre for Cellular and Molecular Biology, Hyderabad 500007, India
| | - Kattera Himaja
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
- Genome Foundation, Centre for Cellular and Molecular Biology, Hyderabad 500007, India
| | - Mamata Deenadayal
- Infertility Institute and Research Centre, Secunderabad 500063, India
| | | | - Prasun Deb
- Krishna Institute of Medical Sciences, Hyderabad 500016, India
| | - Nalini Gupta
- Institute of Reproductive Medicine, Kolkata 700064, India
| | | | - Pratibha Nallari
- Department of Genetics, Osmania University, Hyderabad 500007, India
| | - Lalji Singh
- Clinical Research Facility-Medical Biotechnology, Centre for Cellular and Molecular Biology, Annexe II, Hyderabad 500007, India
- Genome Foundation, Centre for Cellular and Molecular Biology, Hyderabad 500007, India
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Djordjević VA, Jovanović JV, Pavković-Lučić SB, Drakulić DD, Djurović MM, Gotić MD. Cytogenetic findings in Serbian patients with Turner's syndrome stigmata. GENETICS AND MOLECULAR RESEARCH 2010; 9:2213-21. [PMID: 21064029 DOI: 10.4238/vol9-4gmr953] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Cytogenetic findings are reported for 31 female patients with Turner's syndrome. Chromosome studies were made from lymphocyte cultures. Non-mosaicism 45,X was demonstrated in 15 of these patients, whereas only three were apparently mosaic. Eight patients showed non-mosaic and four patients showed mosaic structural aberrations of the X-chromosome. One non-mosaic case displayed a karyotype containing a small marker chromosome. Conventional cytogenetics was supplemented by fluorescence in situ hybridization (FISH) with an X-specific probe to identify the chromosomal origin of the ring and a 1q12-specific DNA probe to identify de novo balanced translocation (1;9) in one patient. To our knowledge, this is the first finding of karyotype 45,X,t(1;9)(cen;cen)/46,X,r(X),t(1;9)(cen;cen) in Turner's syndrome. The same X-specific probe was also used to identify a derivative chromosome in one patient.
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Affiliation(s)
- V A Djordjević
- Clinic of Hematology, Clinical Center of Serbia, Belgrade, Serbia.
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Rodríguez L, Diego-Alvarez D, Lorda-Sanchez I, Gallardo FL, Martínez-Fernández ML, Arroyo-Muñoz ME, Martínez-Frías ML. A small and active ring X chromosome in a female with features of Kabuki syndrome. Am J Med Genet A 2008; 146A:2816-21. [PMID: 18925662 DOI: 10.1002/ajmg.a.32521] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A ring X chromosome is found in about 6% of patients with Turner syndrome (TS), often with mosaicism for a 45,X cell line. Patients with this karyotype are reported to have a higher incidence of a more severe phenotype including mental retardation. In fact, some studies have shown a correlation between this severity and the presence or absence of an intact and functional X inactivation center (XIST). However, the phenotype of the individuals with r(X) cannot be entirely defined in terms of their X-inactivation patterns. Nevertheless, a small group of these patients have been described to manifest clinical features reminiscent of the Kabuki syndrome. Here we present a female patient with clinical features resembling Kabuki syndrome and a mos 45,X/46,X,r(X) karyotype. Methylation analyses of polymorphic alleles of the androgen receptor gene showed that both alleles were unmethylated suggesting an active ring chromosome. A specific X chromosome array CGH was performed estimating the size of the ring to be 17 Mb, lacking the XIST gene, and including some genes with possible implications in the phenotype of the patient.
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Affiliation(s)
- L Rodríguez
- Estudio Colaborativo Español de Malformaciones Congénitas, Centro de Investigación sobre Anomalías Congénitas, Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo, Madrid, Spain.
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Shchelochkov OA, Cooper ML, Ou Z, Peacock S, Yatsenko SA, Brown CW, Fang P, Stankiewicz P, Cheung SW. Mosaicism for r(X) and der(X)del(X)(p11.23)dup(X)(p11.21p11.22) provides insight into the possible mechanism of rearrangement. Mol Cytogenet 2008; 1:16. [PMID: 18655707 PMCID: PMC2518151 DOI: 10.1186/1755-8166-1-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Accepted: 07/25/2008] [Indexed: 01/26/2023] Open
Abstract
We report a patient with a unique and complex cytogenetic abnormality involving mosaicism for a small ring X and deleted Xp derivative chromosome with tandem duplication at the break point. The patient presented with failure to thrive, muscular hypotonia, and minor facial anatomic anomalies, all concerning for Turner syndrome. Brain MRI revealed mild thinning of the corpus callosum, an apparent decrease in ventricular white matter volume, and an asymmetric myelination pattern. Array comparative genome hybridization analysis revealed mosaicism for the X chromosome, deletion of the short arm of an X chromosome, and a duplication of chromosome region Xp11.21-p11.22. G-banded chromosome and FISH analyses revealed three abnormal cell lines: 46,X,der(X)del(X)(p11.23)dup(X)(p11.21p11.22)/46,X,r(X)(q11.1q13.1)/45,X. The small ring X chromosome was estimated to be 5.2 Mb in size and encompassed the centromere and Xq pericentromeric region. X chromosome inactivation (XCI) studies demonstrated a skewed pattern suggesting that the ring X remained active, likely contributing to the observed clinical features of brain dysmyelination. We hypothesize that a prezygotic asymmetric crossing over within a loop formed during meiosis in an X chromosome with a paracentric inversion resulted in an intermediate dicentric chromosome. An uneven breakage of the dicentric chromosome in the early postzygotic period might have resulted in the formation of one cell line with the X chromosome carrying a terminal deletion and pericentromeric duplication of the short arm and the second cell line with the X chromosome carrying a complete deletion of Xp. The cell line carrying the deletion of Xp could have then stabilized through self-circularization and formation of the ring X chromosome.
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Affiliation(s)
- Oleg A Shchelochkov
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.
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Sudden death in a patient with mosaic ring X Turner syndrome and a neuronal migration disorder. Clin Dysmorphol 2007; 17:69-71. [PMID: 18049086 DOI: 10.1097/mcd.0b013e32823b007f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
Global descriptors of the cognitive phenotype of Turner syndrome are well established and are thus commonly referred to. For example, Turner syndrome is a proposed etiology of the nonverbal learning disability - because of reported relative strengths in verbal skills, and relatively weaker nonverbal skills - particularly in arithmetic, select visuospatial skills, and processing speed. This profile is observed throughout and beyond the school age years. Reliance on this gross level description of the cognitive profile (e.g., nonverbal learning disability) may be helpful as a starting point when determining whether an individual with Turner syndrome has educational needs, but it carries limited practical significance when determining the specific nature of these needs. The limitations stem from the fact that the severity of the cognitive profile is highly variable among individuals with Turner syndrome; that the "nonverbal" difficulties are specific rather than widespread; and that any individual with Turner syndrome may also manifest cognitive characteristics independent of Turner syndrome. In view of the increased risk for specific cognitive difficulties, a detailed assessment prior to the onset of formal schooling (or at the time of diagnosis, when diagnosis occurs after 5 years of age) can play an important role in determining school readiness and potential need for educational support among individual girls with Turner syndrome.
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Wiktor AE, Van Dyke DL. Detection of low level sex chromosome mosaicism in Ullrich–Turner syndrome patients. Am J Med Genet A 2005; 138A:259-61. [PMID: 16158437 DOI: 10.1002/ajmg.a.30954] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Ullrich-Turner syndrome (UTS) is most commonly due to a 45,X chromosome defect, but is also seen in patients with a variety of X-chromosome abnormalities or 45,X/46,XY mosaicism. The phenotype of UTS patients is highly variable, and depends largely on the karyotype. Patients are at an increased risk of gonadoblastoma when a Y-derived chromosome or chromosome fragment is present. Since constitutional mosaicism is present in approximately 50% of UTS patients, the identification of minor cell populations is clinically important and a challenge to laboratories. We identified 50 females with a 45,X karyotype as the sole abnormality or as part of a more complex karyotype. Twenty two (44%) had a 45,X karyotype; mosaicism for a second normal or structurally abnormal X was observed in 24 (48%) samples, and mosaicism for Y chromosomal material in 4 (8%) cases. To further investigate the possibility of mosaicism in the 22 patients with an apparently non-mosaic 45,X karyotype, we performed FISH using centromere probes for the X and Y chromosomes. A minor XX cell line was identified in 3 patients, and the 45,X result was confirmed in 19 samples. No samples with XY mosaicism were identified. We describe our validation process for a FISH assay to be used in clinical practice to identify XX or XY mosaicism. FISH as an adjunct to karyotype analysis provides a sensitive and cost-effective technique to identify sex chromosome mosaicism in UTS patients.
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Affiliation(s)
- Anne E Wiktor
- Cytogenetics Laboratory, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota 55905, USA
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Abstract
We present a female with both Prader-Willi syndrome and Turner's syndrome, a combination not previously reported. We review her clinical presentation and discuss her growth pattern, mental development, and puberty, in relation to her mosaic Turner and Prader-Willi syndromes.
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Affiliation(s)
- Roshanak Monzavi
- Center for Endocrinology, Diabetes, and Metabolism, Childrens Hospital Los Angeles, Department of Pediatrics, USC Keck School of Medicine, Los Angeles, CA, USA
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Leppig KA, Sybert VP, Ross JL, Cunniff C, Trejo T, Raskind WH, Disteche CM. Phenotype and X inactivation in 45,X/46,X,r(X) cases. Am J Med Genet A 2005; 128A:276-84. [PMID: 15216549 DOI: 10.1002/ajmg.a.30002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We studied a new series of 21 individuals mosaic for a ring X chromosome [r(X)]. Of nine individuals with mental retardation, only one had a r(X) that lacked XIST (X-inactive-specific transcript) and was not subject to X inactivation, which would explain the abnormal phenotype; the remaining eight cases had XIST on their r(X). The majority of cases (five of seven) with mental retardation had an apparently early replicating r(X); but the androgen receptor gene (AR) was methylated on one allele in five of six informative cases, including two cases with an early replicating r(X). These conflicting results on two indicators of X inactivation suggest a potential dissociation between late replication and DNA methylation in these r(X) chromosomes, which may fail to become completely silenced. Of the twelve subjects who were not mentally retarded, all had XIST present on their r(X) and most (8/10) showed a late replicating r(X), together with AR methylation in all five informative cases, indicating r(X) inactivation. Thus, the unusual phenotypic features and mental retardation associated with the presence of a r(X) cannot be explained solely on the basis of presence or absence of XIST. The r(X) in cases with mental retardation were consistently smaller than those in individuals with normal intelligence, perhaps indicating inability for small rings to undergo structural changes associated with complete X inactivation or lethality in cases with a large non-inactivated r(X). Of the Turner syndrome features present in the r(X) cases, only edema was present in a lesser frequency than in 45,X individuals. Our cases generally had a less severe phenotype than those previously reported, suggesting that reported incidences of abnormalities may be influenced by ascertainment bias, with mental retardation potentially unrelated to the presence of the r(X) in some cases.
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MESH Headings
- Adolescent
- Adult
- Cells, Cultured
- Child
- Child, Preschool
- Chromosomes, Human, X/genetics
- Chromosomes, Human, X/metabolism
- DNA Methylation
- DNA Replication/genetics
- Dosage Compensation, Genetic
- Gene Expression
- Humans
- In Situ Hybridization, Fluorescence
- Infant
- Intellectual Disability/genetics
- Karyotyping
- Lymphocytes/chemistry
- Middle Aged
- Phenotype
- RNA, Long Noncoding
- RNA, Messenger/analysis
- RNA, Untranslated/genetics
- Receptors, Androgen/genetics
- Ring Chromosomes
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Affiliation(s)
- Kathleen A Leppig
- Genetic Services, Group Health Permanente, Seattle, Washington 98112, USA.
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Abstract
Turner's syndrome (TS) is a common genetic disorder of girls and women, for which the defining clinical triad is short stature, impaired sexual development, and infertility. Although classically known as monosomy X, genetic heterogeneity is frequent in TS, with mosaicism conferring a survival advantage. Several genetic loci have been implicated in TS including the short stature homeobox gene. TS effects many organs, with cutaneous stigmata providing critical clues for early detection of TS. The presence of lymphedema and its cutaneous sequelae are predictive of other systemic disorders, such as cardiac disease. Although an increased number of benign nevi have been reported in TS, the decreased melanoma rate in this population suggests some protective factor is active. Keloids were thought to be prevalent in TS, but recent data suggest otherwise. Autoimmune diseases are common in TS, with a possible increased prevalence of alopecia areata and vitiligo. The following review discusses new insights into the genetics and pathogenesis of this complex disorder, summarizes the major systemic effects, and reviews skin manifestations of TS and their implications.
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Affiliation(s)
- Eve J Lowenstein
- Department of Dermatology, State University New York Health Science Center at Brooklyn, Brooklyn, New York 11203, USA.
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23
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Kurosawa K, Harada N, Sosonkina N, Niikawa N, Matsumoto N, Saitoh S. Unmasking 15q12 deletion using microarray-based comparative genomic hybridization in a mentally retarded boy with r(Y). ACTA ACUST UNITED AC 2004; 130A:322-4. [PMID: 15378544 DOI: 10.1002/ajmg.a.30260] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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24
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Le Caignec C, Boceno M, Joubert M, Winer N, Aubron F, Fallet-Bianco C, Rival JM. Prenatal diagnosis of a small supernumerary, XIST-negative, mosaic ring X chromosome identified by fluorescence in situ hybridization in an abnormal male fetus. Prenat Diagn 2003; 23:143-5. [PMID: 12575022 DOI: 10.1002/pd.553] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Marker or ring X [r(X)] chromosomes of varying size are often found in patients with Turner syndrome. Patients with very small r(X) chromosomes that did not include the X-inactivation locus (XIST) have been described with a more severe phenotype. Small r(X) chromosomes are rare in males and there are only five previous reports of such cases. We report the identification of a small supernumerary X chromosome in an abnormal male fetus. Cytogenetic analysis from chorionic villus sampling was performed because of fetal nuchal translucency thickness and it showed mosaicism 46,XY/47,XY,+r(X)/48,XY,+r(X),+r(X). Fluorescence in situ hybridizations (FISH) showed the marker to be of X-chromosome origin and not to contain the XIST locus. Additional specific probes showed that the r(X) included a euchromatic region in proximal Xq. At 20 weeks gestation, a second ultrasound examination revealed cerebral abnormalities. After genetic counselling, the pregnancy was terminated. The fetus we describe is the first male with a mosaic XIST-negative r(X) chromosome identified at prenatal diagnosis. The phenotype we observed was probably the result of functional disomy of the genes in the r(X) chromosome, secondary to loss of the XIST locus.
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Affiliation(s)
- C Le Caignec
- Service de Génétique médicale, Centre Hospitalo-Universitaire, CHU Nantes, 9 quai Moncousu, 44093 Nantes cedex, France.
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25
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Abstract
Turner's syndrome (TS), caused by an absent or structurally abnormal X chromosome, affects 1 in 2500 live female births. Most medical attention has focused on the attainment of final height in childhood and, when this has been achieved, many women are discharged to primary care. It has become increasingly evident that adults with Turner's syndrome are susceptible to a range of disorders such as osteoporosis, hypothyroidism and diabetes. Because of these, and because of the need for long-term oestrogen replacement, it seems most practical for adult health surveillance in TS to come under the remit of the endocrinologist. It must be accepted, however, that the reduced life expectancy in women with TS is largely accounted for by cardiovascular disease. Also, the commonly observed social isolation in adults with TS can be linked to deafness that is increasingly prevalent in an ageing group. Co-ordination of all these issues requires a dedicated multidisciplinary clinic along the lines of those in place in diabetes.
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Affiliation(s)
- Gerard S Conway
- Department of Endocrinology, Middlesex Hospital, Mortimer Street, London, WIN 8AA, UK
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26
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Monroy N, López M, Cervantes A, García-Cruz D, Zafra G, Canún S, Zenteno JC, Kofman-Alfaro S. Microsatellite analysis in Turner syndrome: parental origin of X chromosomes and possible mechanism of formation of abnormal chromosomes. AMERICAN JOURNAL OF MEDICAL GENETICS 2002; 107:181-9. [PMID: 11807897 DOI: 10.1002/ajmg.10113] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Turner syndrome is a chromosomal disorder in which all or part of one X chromosome is missing. The meiotic or mitotic origin of most cases remains unknown due to the difficulty in detecting hidden mosaicism and to the lack of meiotic segregation studies. We analyzed 15 Turner patients, 10 with a 45,X whereas the rest had a second cell line with abnormal X-chromosomes: a pseudodicentric, an isochromosome, one large and one small ring, and the last with a long arm deletion. Our aims were: to detect X cryptic mosaicism in patients with a 45,X constitution; to determine the parental origin of the abnormality; to infer the zygotic origin of the karyotype and to suggest the timing and mechanism of the error(s) leading to the formation of abnormal X chromosomes from maternal origin. Molecular investigation did not revealed heterozygosity for any microsatellite, excluding X mosaicism in the 45,X cases. Parental origin of the single X chromosome was maternal in 90% of these patients. Three of the structurally abnormal Xs were maternally derived whereas the other two were paternal. These results allowed us to corroborate breakpoints in these abnormal X chromosomes and suggest that the pseudodicentric chromosome originated from post-zygotic sister chromatid exchange, whereas the Xq deleted chromosome probably arose after a recombination event during maternal meiosis.
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Affiliation(s)
- Nancy Monroy
- Servicio de Genética, Hospital General de México/Facultad de Medicina, UNAM, México, D.F, México
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27
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Tomkins DJ, McDonald HL, Farrell SA, Brown CJ. Lack of expression of XIST from a small ring X chromosome containing the XIST locus in a girl with short stature, facial dysmorphism and developmental delay. Eur J Hum Genet 2002; 10:44-51. [PMID: 11896455 DOI: 10.1038/sj.ejhg.5200757] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2001] [Revised: 11/21/2001] [Accepted: 11/22/2001] [Indexed: 02/07/2023] Open
Abstract
A 46,X,r(X) karyotype was found in a three and a half year old girl with short stature, facial dysmorphism and developmental delay. The clinical findings were consistent with the phenotype described in a limited number of patients with small ring X chromosomes lacking the XIST locus, a critical player in the process of X chromosome inactivation. Surprisingly, in our patient, fluorescent in situ hybridisation demonstrated that the XIST locus was present on the ring X. However, expression studies showed that there was no XIST transcript in peripheral blood cells, suggesting that the ring X had not been inactivated. This was confirmed by the demonstration that both of the patient's alleles for the androgen receptor gene were unmethylated, and that both of the patient's ZXDA alleles were expressed. The active nature of the ring X would presumably result in overexpression of genes that may account for the developmental delay observed for the patient. Using polymorphic markers along the X chromosome, the ring X was determined to be of paternal origin with one breakpoint in the long arm between DXS8037 and XIST and one in the short arm in Xp11.2 between DXS1126 and DXS991. To attempt to determine why the XIST gene failed to be expressed, the promoter region was sequenced and found to have a base change at the same location as a variant previously associated with nonrandom X chromosome inactivation. This mutation was not seen in over one hundred normal X chromosomes examined; however, it was observed in the paternal grandmother who did not show substantial skewing of X chromosome inactivation.
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Affiliation(s)
- Darrell J Tomkins
- Department of Medical Genetics, University of Alberta and Cytogenetics Laboratory, Stollery Children's Hospital, Edmonton, AB, Canada.
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Cervantes A, Guevara-Yáñez R, López M, Monroy N, Aguinaga M, Valdez H, Sierra C, Canún S, Guízar J, Navarrete C, Zafra G, Salamanca F, Kofman-Alfaro S. PCR-PRINS-FISH analysis of structurally abnormal sex chromosomes in eight patients with Turner phenotype. Clin Genet 2001; 60:385-92. [PMID: 11903342 DOI: 10.1034/j.1399-0004.2001.600512.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
According to cytogenetic analysis, about 50% of Turner individuals are 45,X. The remaining cases have a structurally abnormal X chromosome or are mosaics with a second cell line containing a normal or abnormal sex chromosome. In these mosaics, approximately 20% have a sex marker chromosome whose identity cannot usually be determined by classical cytogenetic methods, requiring the use of molecular techniques. Polymerase chain reaction (PCR), primed in situ labeling (PRINS), and fluorescence in situ hybridization (FISH) analyses were performed in 8 patients with Turner syndrome and 45,X mosaic karyotypes to determine the origin and structure of the marker chromosome in the second cell line. Our data showed that markers were Y-derived in 2 patients and X-derived in the remaining 6 patients. We were also able to determine the breakpoints in the two Y chromosomes. The use of cytogenetic and molecular techniques allowed us to establish unequivocally the origin, X or Y, of the marker chromosomes in the 8 patients with Turner phenotype. This study illustrates the power of resolution and utility of combined cytogenetic and molecular approaches in some clinical cases.
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Affiliation(s)
- A Cervantes
- Servicio de Genética Hospital General de Mexico SS, Facultad de Medicina UNAM, DF, Mexico.
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29
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Stankiewicz P, Thiele H, Giannakudis I, Schlicker M, Baldermann C, Krüger A, Dörr S, Starke H, Hansmann I. Kabuki syndrome-like features associated with a small ring chromosome X and XIST gene expression. AMERICAN JOURNAL OF MEDICAL GENETICS 2001; 102:286-92. [PMID: 11484209 DOI: 10.1002/ajmg.1462] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Although clinical features in Kabuki syndrome (KS; Niikawa-Kuroki syndrome) have been well defined, the underlying genetic mechanism still remains unclear. We report a 9-year-old girl with typical KS-like facial appearance, skeletal and dermatoglyphic abnormalities, severe mental retardation, and growth deficiency. In 60 of 100 GTG-banded metaphases from peripheral blood lymphocytes, a ring chromosome smaller than a G group chromosome was found, which, according to reverse painting, consisted of Xq11.1q13. The proband's karyotype was described as mos45,X/46,X,+r(X). Several loci were analyzed with fluorescence in situ hybridization (FISH) and microsatellite markers revealing that one r(X) breakpoint mapped proximal to DXS422 (Xp11.21) and the second mapped distal to XIST gene, between loci DXS128E and DXS441 (Xq13.2). Uniparental disomy for X and r(X) was excluded and the paternal origin of r(X) was identified. XIST expression was demonstrated by nested reverse transcription polymerase chain reaction (RT-PCR) using primers spanning exons 5, 6i, and 6 in RNA prepared from lymphocytes. The observation of XIST expression is in contrast to two other cases in which the XIST gene was either not present on r(X) or not expressed. To our knowledge, this is the first case of Kabuki-like syndrome manifestations with r(X) and XIST expression.
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Affiliation(s)
- P Stankiewicz
- Institute of Human Genetics and Medical Biology, University Halle-Wittenberg, Halle/S, Germany.
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Gray BA, Bent-Williams A, Wolff DJ, Zori RT. A non-sex chromosome marker in a patient with an atypical Ullrich-Turner phenotype and mosaicism of 46,X,mar/46,XX. Clin Genet 2001; 60:73-6. [PMID: 11531974 DOI: 10.1034/j.1399-0004.2001.600112.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The absence of a sex chromosome in conjunction with the presence of a marker chromosome generally implicates a sex chromosome origin for such marker chromosomes. These types of findings are frequently associated with Ullrich-Turner syndrome. We report a patient that presented with an atypical Ullrich-Turner phenotype and a cytogenetic mosaicism of 46,X,mar/46,XX. The marker chromosome was derived from chromosome 20, not from the X or Y chromosome. The patient's clinical features are described and discussed relative to the cytogenetic findings. This case further demonstrates the necessity of marker chromosome identification for accurate phenotype-karyotype correlation.
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Affiliation(s)
- B A Gray
- Division of Genetics, Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL 32610, USA.
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31
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Yoshizawa A, Ogata T, Yokoya S. Mental Retardation in A Girl with Turner's Syndrome with An Active Ring X Chromosome Missing XIST. Clin Pediatr Endocrinol 2001. [DOI: 10.1297/cpe.10.131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
| | - Tsutomu Ogata
- Department of Pediatrics, Tokyo Electric Power Company Hospital
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Robertson A, Singh RH, Guerrero NV, Hundley M, Elsas LJ. Outcomes analysis of verbal dyspraxia in classic galactosemia. Genet Med 2000; 2:142-8. [PMID: 11397328 DOI: 10.1097/00125817-200003000-00005] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PURPOSE This study evaluates a genotype/phenotype relationship between developmental verbal dyspraxia (DVD) and the common, missense mutation of the galactose-1-phosphate uridyltransferase gene, Q188R, in patients with classic galactosemia (G/G). METHODS As part of this study, we devised a questionnaire for "speech problems" to be completed by the patient\'s clinician. To validate the questionnaire and determine its accuracy in detecting DVD, we analyzed questionnaire responses for 21 patients by testing them independently and directly for DVD through a speech pathologist blinded to the patients' genotype. RESULTS We found that the questionnaire had a sensitivity of 0.56 and a specificity of 0.75. We then calculated the prevalence of DVD for a larger set of 113 patients with G/G galactosemia whose biochemical phenotype, molecular genotypes, and clinical status were known. The prevalence of "speech problems" from raw data were 50 of 113 (44.2%). After adjusting for misclassification, 43 (38.1%) were classified as cases of DVD. Using multivariate, logistic, regression analyses we found a significant interaction between genotype and mean red blood cell (RBC) galactose-1-phosphate (Gal-1-P). When corrected, using mean RBC Gal-1-P < h 3.28 mg%, the Q188R/Q188R genotype was the best predictor of DVD. There was a significant risk (odds ratio = 9.6, p = 0.0504) of having DVD associated with homozygosity for Q188R compared with other genotypes. CONCLUSIONS We conclude that homozygosity for Q188R mutations in the GALT gene is a significant risk factor for DVD. However, poor metabolic control obviates this relationship as indicated by RBC Gal-1-P greater than 3.28 mg%.
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Affiliation(s)
- A Robertson
- Department of Epidemiology, Emory University School of Public Health, Atlanta, Georgia, USA
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Wolff DJ, Schwartz S, Carrel L. Molecular determination of X inactivation pattern correlates with phenotype in women with a structurally abnormal X chromosome. Genet Med 2000; 2:136-41. [PMID: 11397327 DOI: 10.1097/00125817-200003000-00004] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE To correlate the X inactivation pattern, as determined by one or more molecular assays, with phenotype in individuals with structurally abnormal X chromosomes. METHODS We utilized methylation analysis of androgen receptor (AR) and Fragile X (FMR1) genes and expression studies of an XIST polymorphism to assess X inactivation patterns of 28 females with structurally abnormal X chromosomes. Individuals were placed in one of three categories: (1) completely nonrandom inactivation of one X chromosome, (2) preferential or skewed inactivation of one X chromosome, or (3) random inactivation of either X chromosome. RESULTS In 19 of 21 cases with complete (>97%) skewing of X inactivation, the phenotype was either normal, consistent with a single gene disorder, or consistent with classical Turner syndrome; two cases with completely nonrandom X inactivation had unexplained mental retardation phenotypes. In contrast, six of seven cases that did not exhibit completely nonrandom X inactivation were phenotypically abnormal. Carriers of two balanced translocations, two duplicated Xs, one deleted X, and one 45,X/46,X,r(X) presented with mental retardation and/or multiple congenital anomalies. CONCLUSION In patients with random or skewed X inactivation, the abnormal phenotype was hypothesized to be due to functional nullisomy or disomy of X-linked genes. Based on these results, we propose that X inactivation studies should be performed on all women with structurally abnormal X chromosomes. This should aid in the understanding of abnormal phenotypes in liveborn individuals with abnormal X chromosomes and may help to predict phenotypes for prenatally detected cases in the future.
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Affiliation(s)
- D J Wolff
- Department of Genetics and Center for Human Genetics, Case Western Reserve University School of Medicine and University Hospitals of Cleveland, , Ohio, USA
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Migeon BR, Ausems M, Giltay J, Hasley-Royster C, Kazi E, Lydon TJ, Engelen JJ, Raymond GV. Severe phenotypes associated with inactive ring X chromosomes. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/1096-8628(20000703)93:1<52::aid-ajmg9>3.0.co;2-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
BACKGROUND Hypomelanosis of Ito (HI) is a neurocutaneous phenotype that reflects different mosaicisms, including functional imbalances secondary to chromosome-X inactivation patterns in certain X;autosome translocation carriers. METHODS We assessed X inactivation patterns by means of the human androgen receptor (HUMARA) assay and BrdU labeling in affected and unaffected skin of a young female with HI and a de novo t(X;13)(Xp13q;Xq13p). PCR analysis was carried out in DNA extracted from uncultured and cultured skin, whereas the BrdU replication patterns were sought in cultured fibroblasts. Parental DNA was also tested. Fluorescence in situ hybridization (FISH) with X and 13/21 centromere probes (DXZ2 and D13Z1/D21Z1) and a cosmid for the X inactivation center were also performed to refine breakpoint assignments. RESULTS An X inactivation pattern implying functional Xpter-->q11 disomy was found in DNA extracted from uncultured hypopigmented skin, whereas preferential inactivation of the normal X was observed in uncultured normal skin as well as in cultured fibroblasts (after one passage) from both affected and unaffected skin areas. PCR analysis also showed paternal origin of the translocation. BrdU labeling of metaphases from hypopigmented and normal skin primary cultures showed der(Xq13p) to be inactive in about 25% of the cells. FISH revealed that der(Xp13q) had a compound centromere, whereas der(Xq13p) retained 13 centromere repeats but lacked X centromere sequences. Hence, breakpoints were assigned to Xq11 and 13q10. The X inactivation center cosmid gave a signal on both normal X and der(Xp13q), indicating that the inactivation center was not disrupted by the translocation. CONCLUSIONS These findings confirm that mosaic functional Xp disomy, rather than disruption of X-linked genes, is associated with HI and involvement of the central nervous system (CNS) in some carriers of a structurally balanced X;autosome translocation.
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Affiliation(s)
- H Rivera
- División de Genética, Instituto Mexicano del Seguro Social (IMSS), Guadalajara, Jalisco, Mexico. hrivera2udgserv.cencar.udg.mx
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El Abd S, Patton MA, Turk J, Hoey H, Howlin P. Social, communicational, and behavioral deficits associated with ring X turner syndrome. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 88:510-6. [PMID: 10490708 DOI: 10.1002/(sici)1096-8628(19991015)88:5<510::aid-ajmg14>3.0.co;2-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We describe the cognitive and behavioral characteristics of five individuals with a ring X chromosome. All subjects had a small active (early replicating) ring X chromosome. The X inactive specific transcript (XIST) locus was confirmed by fluorescent in situ hybridisation (FISH) to be present in all ring X chromosomes. Mental retardation was present in four individuals. All patients with or without mental retardation had a characteristic profile of aggression toward self and others, episodes of screaming, attentional problems, and impulsiveness. Autistic-like features were also present in all individuals and included limited communication, obsessive compulsive behavior, and social difficulties. In some cases the obsessive behavior was extreme and incapacitating. This characteristic behavioral profile may aid the diagnosis and future understanding of ring X.
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Affiliation(s)
- S El Abd
- Child and Adolescent Psychiatry, St. George's Hospital Medical School, London, United Kingdom.
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37
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Huang B, Lamb A, Dorian A, Brumblay J, Powell B. Small supernumerary ring X chromosome in a four-month-old girl. AMERICAN JOURNAL OF MEDICAL GENETICS 1999; 85:191-3. [PMID: 10406677 DOI: 10.1002/(sici)1096-8628(19990716)85:2<191::aid-ajmg18>3.0.co;2-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Park JP, Brothman AR, Butler MG, Cooley LD, Dewald GW, Lundquist KF, Palmer CG, Patil SR, Rao KW, Saikevych IA, Schneider NR, Vance GH. Extensive analysis of mosaicism in a case of Turner syndrome: the experience of 287 cytogenetic laboratories. College of American Pathologists/American College of Medical Genetics Cytogenetics Resource Committee. Arch Pathol Lab Med 1999; 123:381-5. [PMID: 10235494 PMCID: PMC6779318 DOI: 10.5858/1999-123-0381-eaomia] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To assemble and interpret karyotype data provided as part of the College of American Pathologists/American College of Medical Genetics Cytogenetics Proficiency Testing Program. DATA SOURCES, EXTRACTION, AND SYNTHESIS The Cytogenetics Resource Committee requested data on all cells analyzed in a 1994 whole-blood specimen challenge. In that study, 287 participating laboratories analyzed a total of 14297 cells derived from a sample drawn from an adult donor with Turner syndrome. This individual had previously been found to have mosaicism, including cell lines with X structural anomalies along with monosomy X, making this an excellent challenge for a multicenter cytogenetic survey. RESULTS AND CONCLUSIONS Analysis of the data from this extensive study revealed mosaicism of up to 10 different sex chromosome complements involving the X chromosome with and without a small ring X or a derivative X chromosome. In the routine cytogenetic analysis performed by the participating laboratories, cell lines observed, in decreasing order of prevalence, included 45,X (n = 8357 cells), 46,X,r(X) (n = 3597), 46,X,der(X)t(X;X) (n = 2237), 46,XX (n = 93), 47,X,r(X),r(X) (n = 5), 47,X,der (X)t(X;X),der(X)t(X;X) (n = 3), 47,XX,r(X) (n = 2), and one observation each of 47,XX,der(X)t(X;X), 47,X,der(X)t (X;X),r(X), and 47,XXX. Our molecular cytogenetic data, as well as detailed analysis of G-banded chromosomes, suggest the nomenclature for these 2 abnormal X chromosomes as r(X)(p11.3q21.3) and der(X)t(X;X)(p11.3;q21.3), and we discuss models for the concomitant formation of these 2 entities. Both the degree of analysis and the extensive mosaicism that was discovered in this study are exceptional, and similar reported cases as well as possible mechanisms for the observed X chromosome instability are reviewed.
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Affiliation(s)
- J P Park
- Department of Pathology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA
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39
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Stavropoulou C, Mignon C, Delobel B, Moncla A, Depetris D, Croquette MF, Mattei MG. Severe phenotype resulting from an active ring X chromosome in a female with a complex karyotype: characterisation and replication study. J Med Genet 1998; 35:932-8. [PMID: 9832041 PMCID: PMC1051487 DOI: 10.1136/jmg.35.11.932] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
We report on the characterisation of a complex chromosome rearrangement, 46,X,del(Xq)/47,X,del(Xq),+r(X), in a female newborn with multiple malformations. Cytogenetic and molecular methods showed that the del(Xq) contains the XIST locus and is non-randomly inactivated in all metaphases. The tiny r(X) chromosome gave a positive FISH signal with UBE1, ZXDA, and MSN cosmid probes, but not with a XIST cosmid probe. Moreover, it has an active status, as shown by a very short (three hour) terminal BrdU pulse followed by fluorescent anti-BrdU antibody staining. The normal X is of paternal origin and both rearranged chromosomes originate from the same maternal chromosome. We suggest that both abnormal chromosomes result from the three point breakage of a maternal isodicentric idic(X)(q21.1). Finally, the phenotype of our patient is compared to other published cases and, despite the absence of any 45,X clone, it appears very similar to those with a 45,X/46,X,r(X) karyotype where the tiny r(X) is active.
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Affiliation(s)
- C Stavropoulou
- INSERM U491, Faculté de Médecine Timone, Marseille, France
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40
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Yorifuji T, Muroi J, Kawai M, Uematsu A, Sasaki H, Momoi T, Kaji M, Yamanaka C, Furusho K. Uniparental and functional X disomy in Turner syndrome patients with unexplained mental retardation and X derived marker chromosomes. J Med Genet 1998; 35:539-44. [PMID: 9678697 PMCID: PMC1051363 DOI: 10.1136/jmg.35.7.539] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We analysed parental origin and X inactivation status of X derived marker (mar(X)) or ring X (r(X)) chromosomes in six Turner syndrome patients. Two of these patients had mental retardation of unknown cause in addition to the usual Turner syndrome phenotype. By FISH analysis, the mar(X)/r(X) chromosomes of all patients retained the X centromere and the XIST locus at Xq13.2. By polymorphic marker analysis, both patients with mental retardation were shown to have uniparental X disomy while the others had both a maternal and paternal contribution of X chromosomes. By RT-PCR analysis and the androgen receptor assay, it was shown that in one of these mentally retarded patients, the XIST on the mar(X) was not transcribed and consequently the mar(X) was not inactivated, leading to functional disomy X. In the other patient, the XIST was transcribed but the r(X) appeared to be active by the androgen receptor assay. Our results suggest that uniparental disomy X may not be uncommon in mentally retarded patients with Turner syndrome. Functional disomy X seems to be the cause of mental retardation in these patients, although the underlying molecular basis could be diverse. In addition, even without unusual dysmorphic features, Turner syndrome patients with unexplained mental retardation need to be investigated for possible mosaicism including these mar(X)/r(X) chromosomes.
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Affiliation(s)
- T Yorifuji
- Department of Paediatrics, Kyoto University Hospital, Japan
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41
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Nowaczyk MJ, Ramsay JA, Mohide P, Tomkins DJ. Multiple congenital anomalies in a fetus with 45,X/46,X,r(X)(p11.22q12) mosaicism. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1096-8628(19980526)77:4<306::aid-ajmg11>3.0.co;2-m] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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42
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Abstract
Turner syndrome (TS) is a sex-chromosome disorder, occurring in 1 in 2500 female births. The principal features of TS are short stature and dysfunctional gonads, resulting in a lack of sex hormones, incomplete pubertal development and impaired fertility. The aim of this paper is to review the literature on the psychological effects of TS. The main areas covered relate to well-being and psychopathology, self-esteem, social functioning, gender identity, partner relations and sexual functioning, coping, family aspects and clinical aspects of cognitive impairment. Research on the psychological effects of medical intervention is described, and the methods used for psychological and educational support are presented. Finally, methodological issues are discussed and areas for future research are proposed.
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Affiliation(s)
- U W Boman
- Department of Pediatrics, University of Göteborg, Sweden
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43
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Manea SR, Gershin IF, Babu A, Willner JP, Desnick RJ, Cotter PD. Mosaicism for a small supernumerary ring X chromosome in a dysmorphic, growth-retarded male: mos47,XXY/48,XXY, +r(X). Clin Genet 1997; 52:432-5. [PMID: 9520254 DOI: 10.1111/j.1399-0004.1997.tb02564.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Supernumerary ring X [r(X)] chromosomes are often found in patients with Turner syndrome. The phenotypic effects of the r(X) chromosome are variable, and largely depend on the presence or absence of the X inactivation (XIST) locus. Ring(X) chromosomes in males are rare and have been previously reported in only four cases, with 47,XY, + r(X) or mos47,XY, +r(X)/46,XY karyotypes. These patients all had developmental delay and dysmorphic features. We describe a 2.5-year-old male patient with facial dysmorphia, growth retardation, microcephaly, global developmental delay, and microphallus. Cytogenetic analysis from peripheral blood lymphocytes and fibroblasts identified mosaicism for two cell lines: mos48,XXY, + r(?X)/47,XXY. Fluorescence in situ hybridization (FISH) with an X chromosome paint showed the ring chromosome to be X chromosome derived. This is the first case of an r(X) chromosome described in a 47,XXY patient. FISH analysis of the r(X) chromosome with an XIST probe showed that the XIST locus was absent. Functional disomy of genes in the r(X) chromosome most likely accounts for the abnormal phenotype in the proband.
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Affiliation(s)
- S R Manea
- Department of Human Genetics, Mount Sinai School of Medicine, New York, NY, USA
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44
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Ross JL, Kushner H, Zinn AR. Discriminant analysis of the Ullrich-Turner syndrome neurocognitive profile. AMERICAN JOURNAL OF MEDICAL GENETICS 1997; 72:275-80. [PMID: 9332653 DOI: 10.1002/(sici)1096-8628(19971031)72:3<275::aid-ajmg4>3.0.co;2-q] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Ullrich-Turner syndrome (UTS), or monosomy X, is a genetic disorder characterized by short stature, gonadal dysgenesis, and a particular neurocognitive profile of normally developed language abilities (particularly verbal IQ) and impaired visual-spatial and/or visual-perceptual abilities. The most frequently described profile in UTS includes difficulty with tasks involving memory and attention, decreased arithmetic skills, and impaired visual spatial processing. We used discriminant function analysis (DFA) to distinguish between the neurocognitive profiles of girls with UTS vs. controls matched for age, height, IQ, and socioeconomic status. DFA is a statistical method for deriving a linear function that optimally weights parameters to permit sensitive and specific differentiation among groups. We developed a modified discriminant function, based on seven cognitive test scores, that successfully discriminated between the UTS and control subjects with a sensitivity of 0.45 and a specificity of 0.97. To validate its performance, we applied the discriminant function to a small group of 45,X UTS subjects (n = 13) and control female subjects (n = 25), ages 7-16 years, who were not part of the previous analyses. The discriminant function (DF) identified 54% of these 13 UTS subjects as having the "UTS neurocognitive profile" and 92% of the 25 control subjects as not having the profile. We also compared the DF scores of UTS girls with various mosaic karyotypes and found that the group with 46,XX mosaicism had significantly higher scores (i.e., closer to normal controls) than the other two mosaic groups (t = 2.86, P < 0.005). The results of this study should be useful for genetic counseling and planning educational programs for girls with UTS.
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Affiliation(s)
- J L Ross
- Department of Pediatrics, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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45
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Schwartz S, Depinet TW, Leana-Cox J, Isada NB, Karson EM, Park VM, Pasztor LM, Sheppard LC, Stallard R, Wolff DJ, Zinn AB, Zurcher VL, Zackowski JL. Sex chromosome markers: characterization using fluorescence in situ hybridization and review of the literature. AMERICAN JOURNAL OF MEDICAL GENETICS 1997; 71:1-7. [PMID: 9215760 DOI: 10.1002/(sici)1096-8628(19970711)71:1<1::aid-ajmg1>3.0.co;2-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Fluorescence in situ hybridization (FISH) using biotin labeled X- and Y-chromosome DNA probes was utilized in the analysis of 23 sex chromosome-derived markers. Specimens were obtained through prenatal diagnosis, because of a presumptive diagnosis of Ullrich-Turner syndrome, mental retardation, and minor anomalies or ambiguous genitalia; three were spontaneous abortuses. Twelve markers were derived from the X chromosome and eleven from the Y chromosome; this demonstrates successfully the value and necessity of FISH utilizing DNA probes in the identification of sex chromosome markers. Both fresh and older slides, some of which had been previously G-banded, were used in these determinations. We have also reviewed the literature on sex chromosome markers identified using FISH.
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Affiliation(s)
- S Schwartz
- Center for Human Genetics, Department of Genetics, Case Western Reserve University, and University Hospitals of Cleveland, Ohio 44106, USA
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46
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Abstract
In mammals, females have a pair of X chromosomes, whereas males have one X chromosome and one Y chromosome, which is much smaller and contains fewer genes than a X chromosome. One of the pair of X chromosomes is inactivated in females. The inactivated X chromosome is late-replicating, heterochromatic, and genetically unexpressed. An X inactivation center (XIC) located at a proximal region on Xq is thought to control inactivation of an X chromosome. There has been increasing scientific interest in the relationship between chromosomal and clinical findings in different chromosomal aberrations, whether affecting the sex chromosomes or the autosomes. The genetic and molecular implications of the karyotype/phenotype controversy have recently been considered with the aim of better understanding the interplay of specific genes carried on different chromosomes in organ development and differentiation. Karyotype/phenotype correlation showed the gradation of severity of clinical phenotype to be related to the number of X chromosomes.
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47
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Guillén DR, Lowichik A, Schneider NR, Cohen DS, Garcia S, Zinn AR. Prune-belly syndrome and other anomalies in a stillborn fetus with a ring X chromosome lacking XIST. AMERICAN JOURNAL OF MEDICAL GENETICS 1997; 70:32-6. [PMID: 9129738 DOI: 10.1002/(sici)1096-8628(19970502)70:1<32::aid-ajmg7>3.0.co;2-t] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ring X chromosomes that lack the X inactivation center and fail to be inactivated have been implicated as a cause of mental retardation and multiple congenital anomalies. We report on a stillborn fetus with karyotype mos45,X/46,X,r(X) and early urethral obstruction or prune-belly sequence, single umbilical artery, limb deficiency, horseshoe kidney, cardiac hypertrophy, persistent left superior vena cava, and axial skeleton abnormalities. Fluorescent in situ hydridization (FISH) studies confirmed that the ring chromosome is X-derived and demonstrated that it lacks the XIST locus. The findings in this fetus are discussed with regard to the spectrum of phenotypes associated with monosomy X and small ring X chromosomes.
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Affiliation(s)
- D R Guillén
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235-8591, USA
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48
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McGinniss MJ, Brown DH, Burke LW, Mascarello JT, Jones MC. Ring chromosome X in a child with manifestations of Kabuki syndrome. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/(sici)1096-8628(19970502)70:1<37::aid-ajmg8>3.0.co;2-o] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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49
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Witchel SF, Wenger SL, Hoffman EP. Molecular and cytogenetic studies of X inactivation in a patient with 46,X,del(X)(q22). J Pediatr Adolesc Gynecol 1997; 10:78-82. [PMID: 9179806 DOI: 10.1016/s1083-3188(97)70055-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We report on a phenotypically normal girl with a deletion of the distal long arm of one X chromosome at Xq22, and spontaneous pubertal development including menarche. This suggests that the distal long arm of the X chromosome is not crucial for ovarian development. Cytogenetic and polymerase chain reaction (PCR) amplification methods both showed preferential inactivation of the deleted X chromosome. The PCR-based assay has the additional advantage of identifying the paternal origin of the deleted X chromosome.
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Affiliation(s)
- S F Witchel
- Department of Pediatrics, Children's Hospital of Pittsburgh, Pennsylvania 15213, USA
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50
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Abd SE, Wilson L, Howlin P, Patton MA, Wintgens AM, Wilson R. Agenesis of the corpus callosum in Turner syndrome with ring X. Dev Med Child Neurol 1997; 39:119-24. [PMID: 9062427 DOI: 10.1111/j.1469-8749.1997.tb07394.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An 8-year-old girl with Turner syndrome and 45,X/46,X,r(X) mosaicism was found to have agenesis of the corpus callosum and various other characteristics including 'kabuki makeup' facial features and mild learning disability. Only two other cases of Turner syndrome associated with agenesis of the corpus callosum have been reported, both in patients with a 45,X karyotype. In both of those patients the constellation of signs differed from those of the present patient in a number of ways. It remains to be confirmed whether there is a higher incidence of CNS malformation in girls who have Turner syndrome with a ring X than has been reported for girls with Turner syndrome in general.
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Affiliation(s)
- S E Abd
- St George's Hospital Medical School, London, UK
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