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Mehawej C, Maalouf JE, Abdelkhalik M, Mahfouz P, Chouery E, Megarbane A. CNV Analysis through Exome Sequencing Reveals a Large Duplication Involved in Sex Reversal, Neurodevelopmental Delay, Epilepsy and Optic Atrophy. Genes (Basel) 2024; 15:901. [PMID: 39062680 PMCID: PMC11275410 DOI: 10.3390/genes15070901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 07/06/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND Duplications on the short arm of chromosome X, including the gene NR0B1, have been associated with gonadal dysgenesis and with male to female sex reversal. Additional clinical manifestations can be observed in the affected patients, depending on the duplicated genomic region. Here we report one of the largest duplications on chromosome X, in a Lebanese patient, and we provide the first comprehensive review of duplications in this genomic region. CASE PRESENTATION A 2-year-old female patient born to non-consanguineous Lebanese parents, with a family history of one miscarriage, is included in this study. The patient presents with sex reversal, dysmorphic features, optic atrophy, epilepsy, psychomotor and neurodevelopmental delay. Single nucleotide variants and copy number variants analysis were carried out on the patient through exome sequencing (ES). This showed an increased coverage of a genomic region of around 23.6 Mb on chromosome Xp22.31-p21.2 (g.7137718-30739112) in the patient, suggestive of a large duplication encompassing more than 60 genes, including the NR0B1 gene involved in sex reversal. A karyotype analysis confirmed sex reversal in the proband presenting with the duplication, and revealed a balanced translocation between the short arms of chromosomes X and 14:46, X, t(X;14) (p11;p11) in her/his mother. CONCLUSIONS This case highlights the added value of CNV analysis from ES data in the genetic diagnosis of patients. It also underscores the challenges encountered in announcing unsolicited incidental findings to the family.
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Affiliation(s)
- Cybel Mehawej
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos P.O. Box 36, Lebanon; (C.M.); (E.C.)
| | - Joy El Maalouf
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos P.O. Box 36, Lebanon; (J.E.M.); (P.M.)
| | - Mohamad Abdelkhalik
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos P.O. Box 36, Lebanon; (J.E.M.); (P.M.)
| | - Peter Mahfouz
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos P.O. Box 36, Lebanon; (J.E.M.); (P.M.)
| | - Eliane Chouery
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos P.O. Box 36, Lebanon; (C.M.); (E.C.)
| | - Andre Megarbane
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos P.O. Box 36, Lebanon; (C.M.); (E.C.)
- Institut Jérôme Lejeune, 75015 Paris, France
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Rjiba K, Slimani W, Gaddas M, Hassine IH, Jelloul A, Khelifa HB, El Amri F, Zaouali M, Mcelreavey K, Saad A, Mougou-Zerelli S. Anomalies in Human Sex Determination: Usefulness of a Combined Cytogenetic Approach to Characterize an Additional Case with Xp Functional Disomy Associated with 46,XY Gonadal Dysgenesis. J Clin Res Pediatr Endocrinol 2023; 15:25-34. [PMID: 35984215 PMCID: PMC9976160 DOI: 10.4274/jcrpe.galenos.2022.2022-3-15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVE Disorders of sexual development (DSD) are a heterogeneous group of genital defects affecting chromosomal, gonadal and anatomical sex. 46,XY DSD is a subset of DSD which covers a wide range of phenotypes in which 46,XY gonadal dysgenesis (GD) is the most severe form. In this study, we report on the clinical and molecular cytogenetic findings of a study on a Tunisian girl with the syndromic form of 46,XY DSD. METHODS This case was a phenotypic female patient having several congenital anomalies including growth retardation. Karyotype, fluorescence in situ hybridization and array Comparative Genome Hybridization (array CGH) were performed. RESULTS The proband exhibited a de-novo 46,X,der(Y) karyotype. Array CGH revealed a pathogenic 27.5Mb gain of an Xp21.2 chromosome segment leading to Xp functional disomy. No deletion was observed in the Y-chromosome. The duplicated region encompassed the NR0B1 (DAX1) and MAGEB genes, located within the dosage sensitive sex (DSS) reversal locus, known as promote genes responsible for human sex reversal and testis repression. The extra-dosage and interactions of these genes with different specific genes could result in the impairment of the male sex pathway. Over-dosage of KAL1 and IL1RAPL1 genes fall within the somatic features observed in the patient. CONCLUSION To the best of our knowledge, we report on the fourth case of Xp21.2-pter duplication within Xp;Yp translocation associated with XY GD. Our findings suggest that when duplicated, the NR0B1 and MAGEB genes could be a major cause of XY GD. Therefore, we emphasize the usefulness of a combined cytogenetic approach in order to provide an accurate genetic diagnosis for those patients having syndromic XY DSD in a clinical setting.
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Affiliation(s)
- Khouloud Rjiba
- Farhat Hached University Hospital, Molecular Genetics and Biology of Reproduction, Laboratory of Human Cytogenetics, Sousse; Higher Institute of Biotechnology of Monastir, University of Monastir, Monastir; Université de Sousse, Faculté de Médecine de Sousse, Unité de Services Communs en Génétique Humaine, Sousse, Tunisia
| | - Wafa Slimani
- Farhat Hached University Hospital, Molecular Genetics and Biology of Reproduction, Laboratory of Human Cytogenetics; Université de Sousse, Faculté de Médecine de Sousse, Unité de Services Communs en Génétique Humaine, Sousse, Tunisia
| | - Meriem Gaddas
- Sousse University, Faculty of Medicine of Sousse, Laboratory of Physiology and Functional Explorations, Sousse, Tunisia
| | - Ikbel Hadj Hassine
- University of Monastir, Higher Institute of Biotechnology, Monastir, Tunisia
| | - Afef Jelloul
- Farhat Hached University Hospital, Molecular Genetics and Biology of Reproduction, Laboratory of Human Cytogenetics, Sousse, Tunisia
| | - Hela Ben Khelifa
- Farhat Hached University Hospital, Molecular Genetics and Biology of Reproduction, Laboratory of Human Cytogenetics, Sousse, Tunisia
| | | | - Monia Zaouali
- Sousse University, Faculty of Medicine of Sousse, Laboratory of Physiology and Functional Explorations, Sousse, Tunisia
| | | | - Ali Saad
- Farhat Hached University Hospital, Molecular Genetics and Biology of Reproduction, Laboratory of Human Cytogenetics; Université de Sousse, Faculté de Médecine de Sousse, Unité de Services Communs en Génétique Humaine, Sousse, Tunisia
| | - Soumaya Mougou-Zerelli
- Farhat Hached University Hospital, Molecular Genetics and Biology of Reproduction, Laboratory of Human Cytogenetics; Université de Sousse, Faculté de Médecine de Sousse, Unité de Services Communs en Génétique Humaine, Sousse, Tunisia,* Address for Correspondence: Farhat Hached University Hospital, Molecular Genetics and Biology of Reproduction, Laboratory of Human Cytogenetics; Université de Sousse, Faculté de Médecine de Sousse, Unité de Services Communs en Génétique Humaine, Sousse, Tunisia Phone: +00216 98 480 488 E-mail:
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Nishi MY, Faria Júnior JAD, Krepischi ACV, de Moraes DR, da Costa SS, Silva ESDN, Costa EMF, Mendonca BB, Domenice S. A Small Supernumerary Xp Marker Chromosome Including Genes NR0B1 and MAGEB Causing Partial Gonadal Dysgenesis and Gonadoblastoma. Sex Dev 2021; 16:55-63. [PMID: 34510040 DOI: 10.1159/000517085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 05/06/2021] [Indexed: 11/19/2022] Open
Abstract
Copy number variations of several genes involved in the process of gonadal determination have been identified as a cause of 46,XY differences of sex development. We report a non-syndromic 14-year-old female patient who was referred with primary amenorrhea, absence of breast development, and atypical genitalia. Her karyotype was 47,XY,+mar/46,XY, and FISH analysis revealed the X chromosome origin of the marker chromosome. Array-CGH data identified a pathogenic 2.0-Mb gain of an Xp21.2 segment containing NR0B1/DAX1 and a 1.9-Mb variant of unknown significance from the Xp11.21p11.1 region. This is the first report of a chromosomal microarray analysis to reveal the genetic content of a small supernumerary marker chromosome detected in a 47,XY,+der(X)/46,XY karyotype in a non-syndromic girl with partial gonadal dysgenesis and gonadoblastoma. Our findings indicate that the mosaic presence of the small supernumerary Xp marker, encompassing the NR0B1/DAX1 gene, may have been the main cause of dysgenetic testes development, although the role of MAGEB and other genes mapped to the Xp21 segment could not be completely ruled out.
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Affiliation(s)
- Mirian Yumie Nishi
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - José Antônia Diniz Faria Júnior
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil,
| | | | - Daniela Rodrigues de Moraes
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Silvia Souza da Costa
- Departamento de Genética e Biologia Evolutiva do Instituto de Biociências da Universidade de São Paulo, São Paulo, Brazil
| | - Elinaelma Suelane do Nascimento Silva
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Elaine Maria Frade Costa
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Berenice Bilharinho Mendonca
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Sorahia Domenice
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular LIM/42, Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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Liu Q, Zhu X, Ma Q, He C, Shao J. A de novo derivative Y chromosome (partial Yq deletion and partial duplication of Yp and Yq) in a female with disorders of sex development. Clin Case Rep 2018; 6:1671-1676. [PMID: 30214739 PMCID: PMC6132170 DOI: 10.1002/ccr3.1613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 04/18/2018] [Accepted: 04/26/2018] [Indexed: 11/07/2022] Open
Abstract
We report an atypical disorders of sex development (DSD) case with no mutation of SYR gene but partial Yq deletion and partial duplication of Yp and Yq. This case emphasizes duplicated region Yp11.2→Yq11.223 with partial deletion of Yq11.223→Yqter most probably perturbed the sex differentiation and led to female phenotype.
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Affiliation(s)
- Qing‐Song Liu
- Department of Clinical LaboratoryAffiliated Hospital of North Sichuan Medical CollegeNanchongSichuanChina
| | - Xing‐Chun Zhu
- Pathogenic Biology and Immunology Experiment Teaching CenterNorth Sichuan Medical CollegeNanchongSichuanChina
| | - Qiang Ma
- Department of Clinical LaboratoryAffiliated Hospital of North Sichuan Medical CollegeNanchongSichuanChina
| | - Cheng He
- Department of Clinical LaboratoryAffiliated Hospital of North Sichuan Medical CollegeNanchongSichuanChina
| | - Jian‐Lan Shao
- Department of Obstetrics and GynecologyAffiliated Hospital of North Sichuan Medical CollegeNanchongSichuanChina
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5
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Taketo T. The role of sex chromosomes in mammalian germ cell differentiation: can the germ cells carrying X and Y chromosomes differentiate into fertile oocytes? Asian J Androl 2016; 17:360-6. [PMID: 25578929 PMCID: PMC4430933 DOI: 10.4103/1008-682x.143306] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The sexual differentiation of germ cells into spermatozoa or oocytes is strictly regulated by their gonadal environment, testis or ovary, which is determined by the presence or absence of the Y chromosome, respectively. Hence, in normal mammalian development, male germ cells differentiate in the presence of X and Y chromosomes, and female germ cells do so in the presence of two X chromosomes. However, gonadal sex reversal occurs in humans as well as in other mammalian species, and the resultant XX males and XY females can lead healthy lives, except for a complete or partial loss of fertility. Germ cells carrying an abnormal set of sex chromosomes are efficiently eliminated by multilayered surveillance mechanisms in the testis, and also, though more variably, in the ovary. Studying the molecular basis for sex-specific responses to a set of sex chromosomes during gametogenesis will promote our understanding of meiotic processes contributing to the evolution of sex determining mechanisms. This review discusses the fate of germ cells carrying various sex chromosomal compositions in mouse models, the limitation of which may be overcome by recent successes in the differentiation of functional germ cells from embryonic stem cells under experimental conditions.
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Affiliation(s)
- Teruko Taketo
- Department of Surgery, Research Institute of MUHC; Department of Biology; Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada
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6
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Trisomy Xp and partial tetrasomy Xq resulting from gain of a rearranged X chromosome in a female fetus: pathogenic or not? Mol Cytogenet 2015. [PMID: 26213575 PMCID: PMC4513972 DOI: 10.1186/s13039-015-0160-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Cytogenetic analysis of chorionic villous sampling revealed a mosaic karyotype with gain of a rearranged X chromosome. Microarray and additional studies indicated that the rearranged X carried an inverted duplication, a deletion and a satellited Xqter. Gain of this rearranged X was confirmed by follow-up amniocentesis and postnatal cord blood sample. A full-term infant girl was delivered and showed normal physical findings at both birth and 21-month follow-up examinations. Late replication studies demonstrated that the rearranged X was inactivated in all abnormal cells analyzed. Skewed X-inactivation may suppress the potentially deleterious effects of genomic imbalance; however, gain of X chromosomes, particularly rearranged X chromosomes, often presents challenges for prenatal genetic counseling. The gradation of clinical phenotype severity generally correlates with the number of additional X chromosomes. However, the X chromosome regions responsible for the abnormal phenotypes are poorly understood. This case will further elucidate the phenotypic effects of X inactivation and X chromosome abnormalities.
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7
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Nistal M, Paniagua R, González-Peramato P, Reyes-Múgica M. Perspectives in Pediatric Pathology, Chapter 5. Gonadal Dysgenesis. Pediatr Dev Pathol 2015; 18:259-78. [PMID: 25105336 DOI: 10.2350/14-04-1471-pb.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
One of the most challenging areas in pediatric testicular pathology is the appropriate understanding and pathological diagnosis of disorders of sexual development (DSD), and in particular, the issue of gonadal dysgenesis. Here we present the main concepts necessary for their understanding and appropriate classification, with extensive genetic correlations.
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Affiliation(s)
- Manuel Nistal
- 1 Department of Pathology, Hospital La Paz, Universidad Autónoma de Madrid, Calle Arzobispo Morcillo #2, Madrid 28029, Spain
| | - Ricardo Paniagua
- 2 Department of Cell Biology, Universidad de Alcala, Madrid, Spain
| | - Pilar González-Peramato
- 1 Department of Pathology, Hospital La Paz, Universidad Autónoma de Madrid, Calle Arzobispo Morcillo #2, Madrid 28029, Spain
| | - Miguel Reyes-Múgica
- 3 Department of Pathology, Children's Hospital of Pittsburgh of UPMC, One Children's Hospital Drive, 4401 Penn Avenue, Pittsburgh, PA 15224, USA
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Baxter RM, Vilain E. Translational genetics for diagnosis of human disorders of sex development. Annu Rev Genomics Hum Genet 2013; 14:371-92. [PMID: 23875799 DOI: 10.1146/annurev-genom-091212-153417] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Disorders of sex development (DSDs) are congenital conditions with discrepancies between the chromosomal, gonadal, and phenotypic sex of the individual. Such disorders have historically been difficult to diagnose and cause great stress to patients and their families. Genetic analysis of human samples has been instrumental in elucidating the molecules and pathways involved in the development of the bipotential gonad into a functioning testis or ovary. However, many DSD patients still do not receive a genetic diagnosis. New genetic and genomic technologies are expanding our knowledge of the underlying mechanism of DSDs and opening new avenues for clinical diagnosis. We review the genetic technologies that have elucidated the genes that are well established in sex determination in humans, discuss findings from more recent genomic technologies, and propose a new paradigm for clinical diagnosis of DSDs.
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Barbaro M, Cook J, Lagerstedt-Robinson K, Wedell A. Multigeneration Inheritance through Fertile XX Carriers of an NR0B1 (DAX1) Locus Duplication in a Kindred of Females with Isolated XY Gonadal Dysgenesis. Int J Endocrinol 2012; 2012:504904. [PMID: 22518125 PMCID: PMC3299259 DOI: 10.1155/2012/504904] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 11/21/2011] [Accepted: 11/21/2011] [Indexed: 11/30/2022] Open
Abstract
A 160 kb minimal common region in Xp21 has been determined as the cause of XY gonadal dysgenesis, if duplicated. The region contains the MAGEB genes and the NR0B1 gene; this is the candidate for gonadal dysgenesis if overexpressed. Most patients present gonadal dysgenesis within a more complex phenotype. However, few independent cases have recently been described presenting with isolated XY gonadal dysgenesis caused by relatively small NR0B1 locus duplications. We have identified another NR0B1 duplication in two sisters with isolated XY gonadal dysgenesis with an X-linked inheritance pattern. We performed X-inactivation studies in three fertile female carriers of three different small NR0B1 locus duplications identified by our group. The carrier mothers did not show obvious skewing of X-chromosome inactivation, suggesting that NR0B1 overexpression does not impair ovarian function. We furthermore emphasize the importance to investigate the NR0B1 locus also in patients with isolated XY gonadal dysgenesis.
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Affiliation(s)
- Michela Barbaro
- Department of Molecular Medicine and Surgery, Karolinska Institut, Karolinska University Hospital, CMM L8:02, 17176 Stockholm, Sweden
- *Michela Barbaro:
| | - Jackie Cook
- Department of Clinical Genetics, Sheffield Children's Hospital, Sheffield S 102 TH, UK
| | - Kristina Lagerstedt-Robinson
- Department of Molecular Medicine and Surgery, Karolinska Institut, Karolinska University Hospital, CMM L8:02, 17176 Stockholm, Sweden
| | - Anna Wedell
- Department of Molecular Medicine and Surgery, Karolinska Institut, Karolinska University Hospital, CMM L8:02, 17176 Stockholm, Sweden
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Thorson L, Bryke C, Rice G, Artzer A, Schilz C, Israel J, Huber S, Laffin J, Raca G. Clinical and molecular characterization of overlapping interstitial Xp21-p22 duplications in two unrelated individuals. Am J Med Genet A 2010; 152A:904-15. [DOI: 10.1002/ajmg.a.33340] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Golabi M, James AW, Desai N, Culver K, Cotter PD. Gardner-Silengo-Wachtel or genito-palato-cadiac syndrome with associated autosomal aneuploidy. Am J Med Genet A 2009; 149A:693-7. [DOI: 10.1002/ajmg.a.32755] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Ghosh A, Higgins L, Larkins SA, Miller C, Ostojic N, Martin WL, Kilby MD. Prenatal diagnosis and prenatal imaging of ade novo46,X,der(Y)t(X;Y)(p22.13;q11.23) leading to functional disomy for the distal end of the X chromosome short arm from Xp22.13 in a phenotypically male fetus with posterior fossa abnormalities. Prenat Diagn 2008; 28:1068-71. [DOI: 10.1002/pd.2089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Knuutila S, Heinonen K, Hongell K, Varonen S, Simell O. A duplication within the critical fertility region of X chromosome in a mentally retarded woman with normal menarche. Hereditas 2008; 101:253-5. [PMID: 6520016 DOI: 10.1111/j.1601-5223.1984.tb00923.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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Lovell-Badge R. The role of Sry in mammalian sex determination. CIBA FOUNDATION SYMPOSIUM 2007; 165:162-79; discussion 179-82. [PMID: 1516467 DOI: 10.1002/9780470514221.ch10] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The testis-determining gene is the Y-linked gene responsible for initiating the developmental pathway leading to testis formation in males. A strategy based on determining the precise chromosomal location of this locus has been used to clone a new gene which has been called SRY in humans (Sry in mice). A variety of studies now show that this is indeed the testis-determining gene. Sry has a spatial and temporal pattern of expression which correlates with the initiation of testis differentiation. The amino acid sequence encoded by the gene suggests that the protein may function as a transcription factor, which fits well with models of sex determination. Some cases of XY sex reversal in humans and mouse have been attributed to mutations in SRY/Sry, indicating that it is normally necessary for testis determination. The finding that a genomic fragment carrying Sry can cause male development in XX mice has proved that Sry is the only gene from the Y chromosome necessary for testis determination.
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Affiliation(s)
- R Lovell-Badge
- Laboratory of Eukaryotic Molecular Genetics, National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK
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Barbaro M, Oscarson M, Schoumans J, Staaf J, Ivarsson SA, Wedell A. Isolated 46,XY gonadal dysgenesis in two sisters caused by a Xp21.2 interstitial duplication containing the DAX1 gene. J Clin Endocrinol Metab 2007; 92:3305-13. [PMID: 17504899 DOI: 10.1210/jc.2007-0505] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
CONTEXT Testis development is a tightly regulated process that requires an efficient and coordinated spatiotemporal action of many factors, and it has been shown that several genes involved in gonadal development exert a dosage effect. Chromosomal imbalances have been reported in several patients presenting with gonadal dysgenesis as part of severe dysmorphic phenotypes. RESULTS We screened for submicroscopic DNA copy number variations in two sisters with an apparent normal 46,XY karyotype and female external genitalia due to gonadal dysgenesis, and in which mutations in known candidate genes had been excluded. By high-resolution tiling bacterial artificial chromosome array comparative genome hybridization, a submicroscopic duplication at Xp21.2 containing DAX1 (NR0B1) was identified. Using fluorescence in situ hybridization, multiple ligation probe amplification, and PCR, the rearrangement was further characterized. This revealed a 637-kb tandem duplication that in addition to DAX1 includes the four MAGEB genes, the hypothetical gene CXorf21, GK, and part of the MAP3K7IP3 gene. Sequencing and analysis of the breakpoint boundaries and duplication junction suggest that the duplication originated through a coupled homologous and nonhomologous recombination process. CONCLUSIONS This represents the first duplication on Xp21.2 identified in patients with isolated gonadal dysgenesis because all previously described XY subjects with Xp21 duplications presented with gonadal dysgenesis as part of a more complex phenotype, including mental retardation and/or malformations. Thus, our data support DAX1 as a dosage sensitive gene responsible for gonadal dysgenesis and highlight the importance of considering DAX1 locus duplications in the evaluation of all cases of 46,XY gonadal dysgenesis.
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Affiliation(s)
- Michela Barbaro
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 17176 Stockholm, Sweden.
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Blecher SR, Erickson RP. Genetics of sexual development: A new paradigm. Am J Med Genet A 2007; 143A:3054-68. [DOI: 10.1002/ajmg.a.32037] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Wolf U, Schempp W, Scherer G. Molecular biology of the human Y chromosome. Rev Physiol Biochem Pharmacol 2005; 121:147-213. [PMID: 1485072 DOI: 10.1007/bfb0033195] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- U Wolf
- Institut für Humangenetik und Anthropologie der Universität, Freiburg, FRG
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Sanlaville D, Vialard F, Thépot F, Vue-Droy L, Ardalan A, Nizard P, Corré A, Devauchelle B, Martin-Denavit T, Nouchy M, Malan V, Taillemite JL, Portnoï MF. Functional disomy of Xp including duplication ofDAX1gene with sex reversal due to t(X;Y)(p21.2;p11.3). Am J Med Genet A 2004; 128A:325-30. [PMID: 15216557 DOI: 10.1002/ajmg.a.30115] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Translocations involving the short arms of the X and Y in human chromosomes are uncommon. One of the best-known consequences of such exchanges is sex reversal in 46,XX males and some 46,XY females, due to exchange in the paternal germline of terminal portions of Xp and Yp, including the SRY gene. Translocations of Xp segments to the Y chromosome result in functional disomy of the X chromosome with an abnormal phenotype and sex reversal if the DSS locus, mapped in Xp21, is present. We describe a 7-month-old girl with severe psychomotor retardation, minor anomalies, malformations, and female external genitalia. Cytogenetic analysis showed a 46,X,mar karyotype. The marker was identified as a der(Y)t(Xp;Yp) by fluorescence in situ hybridisation analysis. Further studies with specific locus probes of X and Y chromosomes made it possible to clarify the break points and demonstrated the presence of two copies of the DAX1 gene, one on the normal X chromosome and one on the der(Y). The karyotype of the child was: 46,X,der(Y)t(X;Y)(p21.2;p11.3). The syndrome resulted from functional disomy Xp21.2-pter, with sex reversal related to the presence of two active copies of the DAX1 gene located in Xp21. Few cases of Xp disomy with sex reversal have been reported, primarily related to Xp duplications with 46,XY karyotype, and less often to Xp;Yq translocations. To our knowledge, our patient with sex reversal and a t(Xp;Yp) is the second reported case.
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19
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Seminara SB, Crowley WF. Genetic approaches to unraveling reproductive disorders: examples of bedside to bench research in the genomic era. Endocr Rev 2002; 23:382-92. [PMID: 12050127 DOI: 10.1210/edrv.23.3.0469] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Despite the rapid advances in medical genetics, many clinicians and investigators remain unaware of the general approaches that can be used to map genes. Although there are specific challenges to using genetic approaches in reproductive medicine, the following report summarizes mapping efforts for three diseases: adrenal hypoplasia congenita, hypergonadotropic ovarian failure, and polycystic ovary syndrome. The themes of rare and novel phenotypes, genetically homogenous populations, and genotype/phenotype correlations are emphasized.
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Affiliation(s)
- Stephanie B Seminara
- Reproductive Endocrine Unit and Harvard-Wide Reproductive Endocrine Sciences Center and National Center for Infertility Research, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
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20
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Kokalj Vokac N, Seme Ciglenecki P, Erjavec A, Zagradisnik B, Zagorac A. Partial Xp duplication in a girl with dysmorphic features: the change in replication pattern of late-replicating dupX chromosome. Clin Genet 2002; 61:54-61. [PMID: 11903357 DOI: 10.1034/j.1399-0004.2002.610111.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In this paper we present the case of a girl at the age of 32 months with dysmorphic features, including general muscular hypotonia, developmental delay and mental retardation. The cytogenetic analysis revealed de novo partial duplication of Xp: 46,X,dup(X)(p11.23-->p22.33: :p11.23-->p22.33). To characterize the duplication, X painting, Kallman (KAL), yeast artificial chromosomes (YACs) and bacterial artificial chromosomes (BACs) covering Xp11.23-->Xp22.33 region were used. Selective inactivation of the abnormal X chromosome using HpaII digestion of the AR gene was evident. After BrdU incorporation the abnormal X was late-replicating in all lymphocytes examined. There was one peculiar exception observed: the break-point region was consistently early replicating. The replicating pattern of this region corresponded to the active X chromosome. Methylation pattern of late replicating X chromosome was studied also using antibodies against 5-methylcytosine. The pattern corresponded to the normally inactive X chromosome, with the exception of the previously observed break-point region which revealed an early replicating pattern with strong fluorescent signal, similar to the pattern of the active X chromosome. The observed phenomenon could lead to the abnormal phenotype of the patient, with some normally inactive genes of the break-point region escaping the inactivation process. The abnormal clinical findings could also be due to tissue-dependent differences in the inactivation pattern.
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Affiliation(s)
- N Kokalj Vokac
- Maribor Teaching Hospital, Laboratory of Medical Genetics, Maribor, Slovenia.
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21
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Matsuo M, Muroya K, Kosaki K, Ishii T, Fukushima Y, Anzo M, Ogata T. Random X-inactivation in a girl with duplication Xp11.21-p21.3: Report of a patient and review of the literature. ACTA ACUST UNITED AC 1999. [DOI: 10.1002/(sici)1096-8628(19990903)86:1<44::aid-ajmg8>3.0.co;2-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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22
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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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23
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Teebi AS, Miller S, Ostrer H, Eydoux P, Colomb-Brockmann C, Oudjhane K, Watters G. Spastic paraplegia, optic atrophy, microcephaly with normal intelligence, and XY sex reversal: a new autosomal recessive syndrome? J Med Genet 1998; 35:759-62. [PMID: 9733035 PMCID: PMC1051429 DOI: 10.1136/jmg.35.9.759] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Two female sibs of first cousin Iranian parents were found to have the syndrome of spastic paraplegia, optic atrophy with poor vision, microcephaly, and normal cognitive development. Karyotype analysis showed a normal female constitution in one and a male constitution (46,XY) in the other. The XY female showed normal female external genitalia, normal uterus and tubes, and streak gonads. SRY gene sequencing was normal. We conclude that the present family probably represents a new autosomal recessive trait of pleiotropic effects including XY sex reversal and adds further evidence for the heterogeneity of spastic paraplegia syndromes as well as sex reversal syndromes.
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Affiliation(s)
- A S Teebi
- Division of Medical Genetics A-608, The Montreal Children's Hospital and McGill University, Quebec, Canada
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24
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Zhang A, Weaver DD, Palmer CG. Molecular cytogenetic identification of four X chromosome duplications. AMERICAN JOURNAL OF MEDICAL GENETICS 1997; 68:29-38. [PMID: 8986272 DOI: 10.1002/(sici)1096-8628(19970110)68:1<29::aid-ajmg6>3.0.co;2-t] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Four cases with previously unidentified X-chromosome abnormalities were studied by standard cytogenetic techniques and FISH in order to demonstrate the origin of the extra segment on the abnormal X chromosomes. All cases were identified as X-chromosome duplications by using a chromosome-specific painting probe. Application of appropriate locus-specific DNA probes as an adjunct to GTG- and RBG-banding proved useful in defining the breakpoints and the extent of the duplications. Although the duplicated X chromosome in female cases was selectively inactivated, as demonstrated by its late-replicating pattern, abnormal clinical findings were manifested in 3 female patients.
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Affiliation(s)
- A Zhang
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis 46202-5251, USA
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25
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Telvi L, Ion A, Carel JC, Desguerre I, Piraud M, Boutin AM, Feingold J, Ponsot G, Fellous M, McElreavey K. A duplication of distal Xp associated with hypogonadotrophic hypogonadism, hypoplastic external genitalia, mental retardation, and multiple congenital abnormalities. J Med Genet 1996; 33:767-71. [PMID: 8880579 PMCID: PMC1050733 DOI: 10.1136/jmg.33.9.767] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An unusual familial case of three sibs with a partial duplication of distal Xp sequences is described. The proband, an 18 year old boy, showed mental retardation, severe dysmorphic features, hypogonadotrophic hypogonadism (HHG), and hypoplastic external genitalia. His karyotype was 46,Y,inv dup(X) (p22.11-->p 22.32). The proband has two sisters each with the same inv dup(Xp) chromosome. Both sisters presented with short stature but were otherwise phenotypically normal. The abnormal X chromosome was inactive in the majority of cells examined. Southern blot dosage analysis indicated a duplication of distal Xp sequences. The proximal breakpoint is located between DXS28 and DXS41, and is therefore at least 2 Mb distal to the DSS locus. The relationship between the phenotype and the Xp duplication is discussed.
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Affiliation(s)
- L Telvi
- Laboratoire de Cytogénétique, Hôpital Saint Vincent de Paul, Paris, France
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26
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Alikaşifoğlu A, Kandemir N, Cağlar M, Kotiloğlu E, Yordam N. Prepubertal gonadoblastoma in a 46,XY female patient with features of Turner syndrome. Eur J Pediatr 1996; 155:653-5. [PMID: 8839718 DOI: 10.1007/bf01957146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
UNLABELLED 46,XY gonadal dysgenesis was diagnosed in a 5.5-year-old phenotypically female patient who had physical and somatic stigmata of Turner syndrome such as webbed neck, low hairline, widely spaced nipples, cubitus valgus and coarctation of the aorta. Bilateral streak gonads were removed and an unsuspected gonadoblastoma was found in right gonad. CONCLUSION The prepubertal development of gonadal neoplasm in patient with Xy gonadal dysgenesis indicated the necessity of gonadectomy at the time of diagnosis.
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Affiliation(s)
- A Alikaşifoğlu
- Hacettepe University, Division of Paediatric Endocrinology, Ankara, Turkey
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27
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Ogata T, Matsuo N. Sex determining gene on the X chromosome short arm: dosage sensitive sex reversal. ACTA PAEDIATRICA JAPONICA : OVERSEAS EDITION 1996; 38:390-8. [PMID: 8840552 DOI: 10.1111/j.1442-200x.1996.tb03513.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The present review article summarizes current knowledge concerning the sex determining gene on Xp21, termed DSS (dosage sensitive sex reversal). The presence of DSS has been based on the finding that, in the presence of SRY, partial active Xp duplications encompassing the middle part of Xp result in sex reversal, whereas those of the distal or proximal part of Xp permit male sex development. Because Klinefelter patients develop as males, it is believed that DSS is normally subject to X-inactivation, and that two active copies of DSS override the function of SRY, resulting in gonadal dysgenesis because of meiotic pairing failure. It may be possible that DSS encodes a target sequence for repressing function of SRY or that DSS is involved in an X chromosome-counting mechanism. Molecular approaches have localized DSS to a 160 kb region and isolated candidate genes such as DAX-1 and MAGE-Xp, but there has been no formal evidence equating the candidate gene with DSS. In addition to its clinical importance, the exploration of DSS must provide a useful clue to phylogenetic studies of sex chromosomes and dosage compensation.
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Affiliation(s)
- T Ogata
- Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan
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28
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Ito T, Kaino Y, Hirai H, Kida K, Nakahori Y, Nakagome Y. Sex reversal in a child with duplication of sex reversing locus on the short arm of the X chromosome (Xp). J Pediatr Endocrinol Metab 1996; 9:429-33. [PMID: 8887155 DOI: 10.1515/jpem.1996.9.3.429] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report a child with a female phenotype possessing a karyotype of 46,XY,13p+. The child had female external genitalia, and manifested severe mental retardation, pulmonary atresia and multiple congenital abnormalities. Laparoscopy revealed the presence of streak gonads and Müllerian structures. Histological examination of the gonads showed ovarian-like stroma with immature seminiferous tubules. Chromosome and gene analyses demonstrated Xp11.23 (or 11.3)-pter duplication and an intact sex determinating factor of Y (SRY). The findings of this case suggest that duplication of Xp causes sex reversal in the presence of SRY.
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Affiliation(s)
- T Ito
- Department of Pediatrics, Ehime University School of Medicine, Japan
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29
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Abstract
Hypomelanosis of Ito is a sporadic multisystem disorder known to be associated in many cases with chromosomal mosaicism. While no particular pattern is generally evident for the specific chromosomes involved in such patients, a subgroup of female patients exists in whom the common factor is the presence of a balanced, constitutional X;autosome translocation, with a cytogenetic breakpoint in the pericentromeric region of the X. It is argued here that the phenotype in these cases results not from the interruption of X linked genes but from the presence of mosaic functional disomy of X sequences above the breakpoint.
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Affiliation(s)
- E Hatchwell
- Wessex Regional Genetics Service, Princess Anne Hospital, Southampton, UK
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30
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Baumstark A, Barbi G, Djalali M, Geerkens C, Mitulla B, Mattfeldt T, de Almeida JC, Vargas FR, Llerena Júnior JC, Vogel W, Just W. Xp-duplications with and without sex reversal. Hum Genet 1996; 97:79-86. [PMID: 8557267 DOI: 10.1007/bf00218838] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Duplications in Xp including the DSS (dosage sensitive sex reversal) region cause male to female sex reversal. We investigated two patients from families with Xp duplications. The first case was one of two sisters with karyotype 46,XY,der(22),t(X;22)(p11.3;p11)mat and unambiguous female genitalia. The living sister was developmentally retarded, and showed multiple dysmorphic features and an acrocallosal syndrome. The second case was a boy with a maternally inherited direct duplication of Xp21.3-pter with the breakpoint close to the DSS locus. He had multiple abnormalities and micropenis, but otherwise unambiguous male genitalia. We performed quantitative Southern blot analysis with probes from Xp22.13 to p21.2 to define the duplicated region. Clinical, cytogenetic, and molecular data from both patients were compared with those of previously reported related cases. A comparison of the extragenital symptoms revealed no differences between patients with or without sex reversal. In both cases, the symptoms were non-specific. Among 22 patients with a duplication in Xp, nine had unambiguous female genitalia and a well-documented duplication of the DSS region. Two patients with duplication of DSS showed ambiguous external genitalia. From these data, we conclude that induction of testicular tissue may start in these patients, but that the type of genitalia depends on the degree of subsequent degeneration by a gene in DSS.
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Affiliation(s)
- A Baumstark
- Abteilung Medizinische Genetik, Universität Ulm, Germany
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31
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Mechanism of sex determination in mammals. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s1067-5701(96)80012-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
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32
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Sex reversal in mammals. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s1067-5701(96)80005-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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33
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McElreavey K, Barbaux S, Ion A, Fellous M. The genetic basis of murine and human sex determination: a review. Heredity (Edinb) 1995; 75 ( Pt 6):599-611. [PMID: 8575930 DOI: 10.1038/hdy.1995.179] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Determination of mammalian sex depends on the presence or absence of a functional testis. Testes are determined by the activity of the testis determining factor encoded by the sex determining gene, Y (SRY) located on the Y chromosome. Considerable evidence suggests that the SRY gene is the only gene on the Y chromosome that is both necessary and sufficient to initiate testis determination. Other steps in the mammalian sex determining pathway are unknown, although recent advances have shown that mutations in X chromosome and autosomal loci are also associated with sex reversal, suggesting the presence of at least one other sex determining gene. Duplications of sequences on the short arm of the human X chromosome, including the DAX-1 (DSS-AHC critical region on the X chromosome, gene 1) gene, are occasionally associated with XY male-to-female sex reversal. In addition, mutations in the SRY-related gene SOX9 (SRY-related box) are associated with a failure of human testicular determination. Furthermore, the occurrence of inherited sex reversed conditions in both mice and men indicate the presence of at least one other sex determining gene. Breeding the Y chromosome from certain Mus musculus domesticus strains into the laboratory mouse strain C57BL/6J results in XY male-to-female sex reversal. This suggests both allelic variation of the Sry gene and the presence of autosomal sex determining genes. In humans, familial cases of SRY-negative XX males occur. Analysis of the transmission of the trait indicates the segregation of an autosomal or X-linked recessive mutation. The mutation may be in a gene whose wild-type function is to inhibit male sex determination. SRY may trigger male sex determination by repressing or functionally antagonizing the product of this gene.
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Affiliation(s)
- K McElreavey
- Immunogénétique Humaine, Institut Pasteur, Paris, France
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34
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Bajalica S, Blennow E, Tşezou A, Galla-Voumvouraki A, Alevizaki M, Sinaniotis C, Kitsiou-Tzeli S. Partial disomy of Xp and the presence of SRY in a phenotypic female. J Med Genet 1995; 32:987-90. [PMID: 8825932 PMCID: PMC1051785 DOI: 10.1136/jmg.32.12.987] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We present a study of a mentally retarded and mildly dysmorphic female in whom initial cytogenetic studies identified the karyotype 46,X, + mar. Further characterisation of the structurally abnormal chromosome by fluorescence in situ hybridisation (FISH) showed that it is composed of both X and Y chromosome material with a centromere originating from the Y chromosome. The presence of the DMD gene and the absence of the XIST gene was shown by FISH using locus specific probes. The Y segment included the SRY and ZFY genes. Based on these findings, the karyotype was defined as 46, X,der(Y)t(X;Y) (p21.1;q11). This case illustrates male to female sex reversal owing to a partial duplication of the short arm of the X chromosome in the presence of SRY.
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Affiliation(s)
- S Bajalica
- Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden
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35
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Palka G, Calabrese G, Mingarelli R, Guanciali Franchi P, Stuppia L, Morizio E, Peila R, Antonucci A. Duplication Xp22.2 and pseudoisodicentric Yq detected by FISH and PCR in a sterile male. Clin Genet 1995; 48:213-6. [PMID: 8591674 DOI: 10.1111/j.1399-0004.1995.tb04091.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A chromosome mosaicism with two cell lines was diagnosed in a sterile man. One cell line had a 45, -Y, dup (X) (p22.2) karyotype and accounted for 83% of lymphocytes analyzed. Fluorescence in situ hybridization (FISH) analysis with specific X and Y probes excluded a translocation between the short arms of the X and Y chromosomes and showed that Xp duplication involved a region containing the DXS85 locus, distal to the ZFX and DSS sites. The other cell line consisted of a diploid karyotype with a rearranged Y chromosome, which was shown to be a pseudoisodicentric Yq by FISH. Moreover, FISH with a specific probe for the AZF locus and polymerase chain reaction using Yq SY108 and SY121 primers showed no signals for this region, possibly accounting for the azoospermia in this patient.
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Affiliation(s)
- G Palka
- Istituti di Biologia e Genetica, CNR Chieti, Italy
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36
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Abstract
The classical conception of the chromosomal mechanism of sex determination presumes a chromosome unique for and determining the heterogametic sex. On the basis of recent evidence, however, this picture is becoming increasingly complex, with a multitude of genes appearing to interact simultaneously or successively to bring about the gonadal phenotype. The genes identified so far that are thought to be involved in the process of human sex determination are distributed on various chromosomes, but the consecution of their function remains to be elucidated. To the Y chromosome only a relative role can be ascribed, and it has not yet been established which gene is on top of the cascade. All of the genes under discussion are involved in transcriptional control, and at least the majority of them appear to exert pleiotropic effects. The regulation of their expression must still be defined, and it will be a long way before a link to gonadal morphogenesis is ultimately found.
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Affiliation(s)
- U Wolf
- Institut für Humangenetik und Anthropologie, Universität Freiburg, Germany
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37
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Affiliation(s)
- A J Schafer
- Department of Genetics, University of Cambridge, United Kingdom
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38
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Foster JW, Dominguez-Steglich MA, Guioli S, Kwok C, Weller PA, Stevanović M, Weissenbach J, Mansour S, Young ID, Goodfellow PN. Campomelic dysplasia and autosomal sex reversal caused by mutations in an SRY-related gene. Nature 1994; 372:525-30. [PMID: 7990924 DOI: 10.1038/372525a0] [Citation(s) in RCA: 1078] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Induction of testis development in mammals requires the presence of the Y-chromosome gene SRY. This gene must exert its effect by interacting with other genes in the sex-determination pathway. Cloning of a translocation chromosome breakpoint from a sex-reversed patient with campomelic dysplasia, followed by mutation analysis of an adjacent gene, indicates that SOX9, an SRY-related gene, is involved in both bone formation and control of testis development.
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Affiliation(s)
- J W Foster
- Department of Genetics, University of Cambridge, UK
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39
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Lahn BT, Ma N, Breg WR, Stratton R, Surti U, Page DC. Xq-Yq interchange resulting in supernormal X-linked gene expression in severely retarded males with 46,XYq- karyotype. Nat Genet 1994; 8:243-50. [PMID: 7874166 DOI: 10.1038/ng1194-243] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The critical importance of dosage compensation is underscored by a novel human syndrome ("XYXq syndrome") in which we have detected partial X disomy, demonstrated supernormal gene expression resulting from the absence of X inactivation, and correlated this overexpression with its phenotypic consequences. Studies of three unrelated boys with 46,XYq- karyotypes and anomalous phenotypes (severe mental retardation, generalized hypotonia and microcephaly) show the presence of a small portion of distal Xq on the long arm of the Y derivative. Cells from these boys exhibit twice-normal activity of glucose-6-phosphate dehydrogenase, a representative Xq28 gene product. In all three cases, the presence of Xq DNA on a truncated Y chromosome resulted from an aberrant Xq-Yq interchange occurring in the father's germline.
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Affiliation(s)
- B T Lahn
- Howard Hughes Research Laboratories at Whitehead Institute, Cambridge, Massachusetts 02142
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40
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Hsu LY. Phenotype/karyotype correlations of Y chromosome aneuploidy with emphasis on structural aberrations in postnatally diagnosed cases. AMERICAN JOURNAL OF MEDICAL GENETICS 1994; 53:108-40. [PMID: 7856637 DOI: 10.1002/ajmg.1320530204] [Citation(s) in RCA: 209] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Over 600 cases with a Y aneuploidy (other than non-mosaic 47,XYY) were reviewed for phenotype/karyotype correlations. Except for 93 prenatally diagnosed cases of mosaicism 45,X/46,XY (79 cases), 45,X/47,XYY (8 cases), and 45,X/46,XY/47,XYY (6 cases), all other cases were ascertained postnatally. Special emphasis was placed on structural abnormalities. This review includes 11 cases of 46,XYp-; 90 cases of 46,XYq- (52 cases non-mosaic; 38 cases 45,X mosaic); 34 cases of 46,X,r(Y) (9 cases non-mosaic and 25 cases 45,X mosaic); 8 cases of 46,X,i(Yp) (4 non-mosaic and 4 mosaic with 45,X); 12 cases of 46,X,i(Yq) (7 non-mosaic and 5 mosaic); 44 cases of 46,X,idic(Yq); 80 cases of 46,X, idic(Yp) (74 cases had breakpoints at Yq11 and 6 cases had breakpoints at Yq12); 130 cases of Y/autosome translocations (50 cases with a Y/A reciprocal translocation, 20 cases of Y/A translocation in 45,X males, 60 cases of Y/DP or Y/Gp translocations); 52 cases of Y/X translocations [47 cases with der(X); 4 cases with der(Y), and 1 case with 45,X with a der(X)], 7 cases of Y/Y translocations; 151 postnatally diagnosed cases of 45,X/46,XY; 14 postnatally diagnosed cases of 45,X/47,XYY; 18 cases of 45,X/46,XY/47,XYY; and 93 aforementioned prenatally diagnosed cases with a 45,X cell line. It is clear that in the absence of a 45,X cell line, the presence of an entire Yp or a region of it including SRY would lead to a male phenotype in an individual with a Y aneuploidy, whereas the lack of Yp invariably leads to a female phenotype with typical or atypical Ullrich-Turner syndrome (UTS). Once there is a 45,X cell line, regardless of whether there is Yp, Yq, or both Yp and Yq, or even a free Y chromosome in other cell line, there is an increased chance for that individual to be a phenotypic female with UTS manifestations or to have ambiguous external genitalia. This review once again shows a major difference in reported phenotypes between postnatally and prenatally diagnosed cases of 45,X/46,XY, 45,X/47,XYY, and 45,X/46,XY/47,XYY mosaicism. It appears that ascertainment bias can explain the fact that all known patients with postnatal diagnosis are phenotypically abnormal, while over 90% of prenatally diagnosed cases are reported to have a normal male phenotype. Further elucidation of major Y genes and their clinical significance can be expected in the rapidly expanding gene mapping projects. More, consequently better, phenotype/karyotype correlations can be anticipated at both the cytogenetic and the molecular level.
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Affiliation(s)
- L Y Hsu
- Prenatal Diagnosis Laboratory of New York City, NY 10016
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41
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Gustashaw KM, Zurcher V, Dickerman LH, Stallard R, Willard HF. Partial X chromosome trisomy with functional disomy of Xp due to failure of X inactivation. AMERICAN JOURNAL OF MEDICAL GENETICS 1994; 53:39-45. [PMID: 7802034 DOI: 10.1002/ajmg.1320530109] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A 5-month-old girl with mild phenotypic abnormalities, developmental delay, and seizures was found to have the de novo karyotype 46,XX,-13,+der(13)t(X;13)(p21.2;p11.1). The partial trisomy of Xp21.2-->pter was confirmed with fluorescence in situ hybridization, using an X chromosome painting probe and several cosmid and YAC probes for Xp sequences. Replication banding showed that one of the structurally normal X chromosomes was late-replicating, but that the Xp segment of the der(13) was early-replicating in all cells examined. Since segments of the X chromosome separated from the X inactivation center in Xq13.2 cannot undergo X inactivation, the result is functional disomy of distal Xp. As the loss of short arm material from chromosome 13 is not considered to be clinically significant, the genomic imbalance of Xp expressed in this patient most likely accounts for her abnormal phenotype.
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Affiliation(s)
- K M Gustashaw
- Department of Genetics, Case Western Reserve University, Cleveland, OH 44106
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42
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Bardoni B, Zanaria E, Guioli S, Floridia G, Worley KC, Tonini G, Ferrante E, Chiumello G, McCabe ER, Fraccaro M. A dosage sensitive locus at chromosome Xp21 is involved in male to female sex reversal. Nat Genet 1994; 7:497-501. [PMID: 7951319 DOI: 10.1038/ng0894-497] [Citation(s) in RCA: 488] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Male to female sex reversal has been observed in individuals with duplications of the short arm of the X chromosome. Here we demonstrate that sex reversal results from the presence of two active copies of an Xp locus rather than from its rearrangement and that alterations at this locus constitute one of the causes of sex reversal in individuals with a normal 46,XY karyotype. We have named this locus DSS (Dosage Sensitive Sex reversal) and localized it to a 160 kilobase region of chromosome Xp21, adjacent to the adrenal hypoplasia congenita locus. The identification of male individuals deleted for DSS suggests that this locus is not required for testis differentiation. We propose that DSS has a role in ovarian development and/or functions as a link between ovary and testis formation.
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43
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Rao PN, Klinepeter K, Stewart W, Hayworth R, Grubs R, Pettenati MJ. Molecular cytogenetic analysis of a duplication Xp in a male: further delineation of a possible sex influencing region on the X chromosome. Hum Genet 1994; 94:149-53. [PMID: 8045561 DOI: 10.1007/bf00202860] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We describe a male infant with severe mental retardation and autism with a duplication of the short arm of the X chromosome. Chromosome painting confirmed the origin of this X duplication. Molecular cytogenetic analysis with fluorescence in situ hybridization (FISH) identified one copy of the zinc finger protein on the X chromosome (ZFX) and two copies of the steroid sulfatase gene (STS), further delineating the breakpoints. Based on cytogenetic and molecular comparisons of cases from the literature of sex-reversal in dup(X),Y patients and our patient, we suggest that a possible secondary sex-influencing gene involved in the regulation of sex determination or testis morphogenesis is present at the distal Xp21.1 to p21.2 region.
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Affiliation(s)
- P N Rao
- Department of Pediatrics, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27157
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44
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Ogata T, Matsuo N. Testis determining gene(s) on the X chromosome short arm: chromosomal localisation and possible role in testis determination. J Med Genet 1994; 31:349. [PMID: 8071967 PMCID: PMC1049821 DOI: 10.1136/jmg.31.4.349] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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45
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Arn P, Chen H, Tuck-Muller CM, Mankinen C, Wachtel G, Li S, Shen CC, Wachtel SS. SRVX, a sex reversing locus in Xp21.2-->p22.11. Hum Genet 1994; 93:389-93. [PMID: 8168809 DOI: 10.1007/bf00201663] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Duplication within Xp21 causes female or intersexual development in human embryos with an XY chromosome complement. We have mapped the responsible gene, SRVX (sex reversal X), in XY-sex-reversed maternal half siblings who had inherited the duplication from their mother. The limited size of the duplication in our cases, relative to its extent in other similar cases, allows assignment of the SRVX locus to Xp21.2-->p22.11. We infer that SRVX is part of a pathway of sex-determining genes that includes SRY and SRA1, the latter recently assigned to chromosome 17q. If mutation of SRA1 or SRVX can reverse the sex of the XY fetus, this would explain why mutation within SRY is found only sporadically in women with XY gonadal dysgenesis.
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Affiliation(s)
- P Arn
- Nemours Children's Clinic, Jacksonville, FL 32247
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46
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McElreavey K, Vilain E, Cotinot C, Payen E, Fellous M. Control of sex determination in animals. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 218:769-83. [PMID: 8281929 DOI: 10.1111/j.1432-1033.1993.tb18432.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- K McElreavey
- Institut Nationale de la Santé et de la Recherche Médicale (INSERM) U276, Université Paris VII, Institut Pasteur, France
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47
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Urioste M, Rodríguez JI, Barcia JM, Martín M, Escribá R, Pardo M, Camino J, Martínez-Frías ML. Persistence of müllerian derivatives, lymphangiectasis, hepatic failure, postaxial polydactyly, renal and craniofacial anomalies. AMERICAN JOURNAL OF MEDICAL GENETICS 1993; 47:494-503. [PMID: 8256813 DOI: 10.1002/ajmg.1320470413] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We describe 3 unrelated newborn males with a previously unreported constellation of congenital anomalies. All 3 died neonatally of hepatic failure. Clinically, they presented with a pattern of malformations characterized by prenatal linear growth deficiency, hypertrophied alveolar ridges, redundant nuchal skin, and postaxial polydactyly. All 3 cases had male external genitalia with cryptorchidism, and 2 of them, a small penis. Necropsies showed similar internal anomalies, consisting of müllerian duct remnants, lymphangiectasis, and renal anomalies. The karyotypes were normal (46, XY) in skin fibroblasts (Case 1) and in peripheral blood lymphocytes (Case 3). Although this pattern of congenital anomalies must be differentiated from several other lethal syndromes, to our knowledge, no similar cases have been described previously. Cause of this syndrome is unknown. Because Case 2 had a previous brother with similar anomalies, we suspect that this new entity probably is an autosomal recessive or X-linked trait.
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Affiliation(s)
- M Urioste
- ECEMC, Facultad de Medicina, Universidad Complutense, Madrid, Spain
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48
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Bardoni B, Floridia G, Guioli S, Peverali G, Anichini C, Cisternino M, Casalone R, Danesino C, Fraccaro M, Zuffardi O. Functional disomy of Xp22-pter in three males carrying a portion of Xp translocated to Yq. Hum Genet 1993; 91:333-8. [PMID: 8099057 DOI: 10.1007/bf00217352] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A number of Xp22;Yq11 translocations involving the transposition of Yq material to the distal short arm of the X chromosome have been described. The reciprocal product, i.e. the derivative Y chromosome resulting from the translocation of a portion of Xp to Yq, has never been recovered. We searched for this reciprocal product by performing dosage analysis of Xp22-pter loci in 9 individuals carrying a non-fluorescent Y chromosome. In three mentally retarded and dysmorphic patients, dosage analysis indicated the duplication of Xp22 loci. Use of the highly polymorphic probe CRI-S232 demonstrated the inheritance of paternal Xp-specific alleles in the probands. In situ hybridization, performed in one case, confirmed that 29CL pseudoautosomal sequences were present, in addition to Xpter and Ypter, in the telomeric portion of Yq. To our knowledge, these are the first cases in which the translocation of Xp material to Yq has been demonstrated. The X and Y breakpoints were mapped in the three patients by dosage and deletion analysis. The X breakpoint falls, in the three cases, in a region of Xp22 that is not recognized as sharing sequence similarities with the Y chromosome, thus suggesting that these translocations are not the result of a homologous recombination event.
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Affiliation(s)
- B Bardoni
- Biologia Generale e Genetica Medica, Università di Pavia, Italy
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49
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Tuck-Muller CM, Martinez JE, Batista DA, Kearns WG, Wertelecki W. Duplication of the short arm of the X chromosome in mother and daughter. Hum Genet 1993; 91:395-400. [PMID: 8500796 DOI: 10.1007/bf00217366] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
An 11-year-old girl with short stature, mental retardation, and mild dysmorphic features was found to have an inverted duplication of most of the short arm of the X chromosome [dic inv dup(X)(qter-->p22.3::p22.3-->cen:)]. Her mother, who is also short and retarded, carries the same duplication. Fluorescence in situ hybridization with an X chromosome library, and with X centromere-specific alpha satellite and telomere probes, was useful in characterizing the duplication. In most females with structurally abnormal X chromosomes, the abnormal chromosome is inactivated. Although the duplicated X was consistently late replicating in the mother, X chromosome inactivation studies in the proband indicated that in 11% of her lymphocytes the duplicated X was active.
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Affiliation(s)
- C M Tuck-Muller
- Department of Medical Genetics, University of South Alabama, College of Medicine, Mobile 36688
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50
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Coles K, Mackenzie M, Crolla J, Harvey J, Starr J, Howard F, Jacobs P. A complex rearrangement associated with sex reversal and the Wolf-Hirschhorn syndrome: a cytogenetic and molecular study. J Med Genet 1992; 29:400-6. [PMID: 1619635 PMCID: PMC1015991 DOI: 10.1136/jmg.29.6.400] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We report a male infant referred with multiple congenital abnormalities consistent with the Wolf-Hirschhorn syndrome. Cytogenetic analysis showed a chromosome complement of 46,XX with a deletion of 4p15.2----4pter and its replacement by material of unknown origin. The patient was positive for a number of Yp probes including SRY, the testis determining factor, and in situ hybridisation localised the Yp material to the tip of the short arm of one X chromosome. Using pDP230, a probe for the pseudoautosomal region, and M27 beta, which recognises a locus in proximal Xp, the material translocated on to 4p was identified as originating from the short arm of the paternal X chromosome. The most reasonable explanation for this complex rearrangement is two separate exchange events involving both chromatids of Xp during paternal meiosis. An aberrant X-Y interchange gave rise to the sex reversal and an X;4 translocation resulted in additional, apparently active Xp material and a deletion of 4p which produced the Wolf-Hirschhorn phenotype.
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Affiliation(s)
- K Coles
- Wessex Regional Genetics Laboratory, Salisbury District Hospital
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