scholarly journals Turner Syndrome with Ring X Chromosome: Do They Have a Distinct Phenotype?

2020 ◽  
Vol 17 (3) ◽  
Author(s):  
Yee Lin Lee ◽  
Salwati Shuib ◽  
Loo Ling Wu
Keyword(s):  
Turner Syndrome ◽  
Cell Lines ◽  
X Chromosome ◽  
The Other ◽  
Ring Size ◽  
Mental Impairment ◽  
Normal Intelligence ◽  
Distinct Phenotype ◽  
Body Tissues ◽  
Mentally Impaired

In contrast to classic Turner syndrome, Turner patients with ring X chromosome are associated with distinct dysmorphism and are likely to be mentally impaired. Four Turner patients with ring X chromosome were examined for phenotypic features of Turner syndrome and additional dysmorphism. Both patients 1 and 2 are twins with normal intelligence whereas patients 3 and 4 have mental impairment. With the exception of patient 4, the other three patients only have few Turner characteristics. None of the patients have the distinctive dysmorphism previously reported in Turner syndrome with ring X chromosome. Both twins developed spontaneous puberty. Patients 3 and 4 however had no spontaneous puberty. We postulate that this variation may be related to the ring size, the proportion of 45,X and ring X chromosome in cell lines of various body tissues as well as the ability of these rings to be inactivated as a result of lyonisation.

CHROMOSOMES AND DNA OF MICROTUS II. CONFIRMATION OF DELETION OF CONSTITUTIVE HETEROCHROMATIN IN M. AGRESTIS CELLS IN VITRO

1977 ◽  
Vol 19 (3) ◽  
pp. 537-541 ◽  
Author(s):  
J. E. K. Cooper
Keyword(s):  
Somatic Cell ◽  
Cell Line ◽  
Cell Lines ◽  
X Chromosome ◽  
Sex Chromosomes ◽  
Constitutive Heterochromatin ◽  
The Other ◽  
Microtus Agrestis ◽  
C Banding

The distribution of constitutive heterochromatin has been examined by C-banding in two somatic cell lines, grown in vitro, from a female Microtus agrestis. One line retains one intact X chromosome together with the short arm of the other X chromosome, while the other cell line retains only the short arm of one X chromosome. Thus, each cell line has lost substantial amounts of heterochromatin from the sex chromosomes, but this material has been deleted from the cells, and not translocated to other chromosomes. Nonetheless, both cell lines continue to propagate well in vitro.

scholarly journals A Rare Variant of Turner Syndrome With Isodicentric X Chromosome Resulting in Trisomy: A Case Report

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A695-A696
Author(s):  
Jacqueline T Chan ◽  
Ma Cristine C Cabanas
Keyword(s):  
Short Stature ◽  
Cell Line ◽  
Turner Syndrome ◽  
Cell Lines ◽  
X Chromosome ◽  
Tissue Transglutaminase ◽  
Genetic Disorder ◽  
Delayed Puberty ◽  
Thyroid Peroxidase ◽  
Abnormal Cell

Abstract Introduction: Turner syndrome is a genetic disorder caused by the loss of an X-chromosome affecting approximately 1 in every 2,500 females. A constitutional karyotype of 45, X accounts for nearly 50% of patients, while mosaicism and other chromosomal structural abnormalities such as deletions, duplications, ring, isodicentric chromosomes, inversions and translocations, have been reported. Isodicentric X chromosomes are formed presumably by end-to-end fusion of chromatids after a break, with subsequent loss of an acentric fragment. These chromosomes in general have phenotypes characteristic of the resultant X deletions. We present a case of a 14-year-old female diagnosed with Turner syndrome and with 2 abnormal cell lines. Case Presentation: This is a case of a 14-year-old female referred to pediatric endocrinology for concerns of short stature and delayed puberty. She denied any food intolerance, bloating and diarrhea. She is otherwise healthy with unremarkable past medical history. Her weight was normal at 15th percentile. Her height was 137cm or 0.01 percentile with a Z score of –3.6. Work up revealed hypothyroidism with TSH 16.3 mcIU/mL (0.4-4.7 mcIU/mL), positive thyroid peroxidase antibody >900 IU/ml and thyroglobulin antibody 14 IU/mL (< 1.8IUm/mL) and celiac disease (tissue transglutaminase IgA > 100 U/mL) both without associated symptoms. Estradiol level was undetectable, and LH and FSH were 9.89 mIU/ml and 52.69 mIU/ml respectively. The rest of her labs including growth factors were normal. Bone age was normal at 13 years for chronological age of 14 years old. Chromosomal microarray revealed 2 abnormal cell lines: one with monosomy X, the other with a normal X chromosome and an isodicentric X chromosome involving the Xp11.22-q28 region resulting in trisomy of the latter cell line. Levothyroxine was started. Plan is to start growth hormone therapy and initiate puberty after. Patient referred to necessary subspecialties for hearing evaluation as well as cardiac evaluation Conclusion Turner syndrome usually presents as females with short stature, gonadal dysgenesis and 45,X cell line that is either singly or in combination with another mosaic cell line. Our patient presented with short stature and absence of puberty. Initial investigation revealed hypothyroidism and highly positive celiac antibodies, but unable to attribute her short stature to both diagnoses given the lack of other symptoms. This case emphasizes the importance of checking the karyotype in females presenting with short stature and more importantly delayed puberty as part of the diagnostic algorithm. In addition, checking thyroid and celiac panel are also imperative as treatment of these are treatable etiologies of short stature.

Extensive Analysis of Mosaicism in a Case of Turner Syndrome

1999 ◽  
Vol 123 (5) ◽  
pp. 381-385
Author(s):  
Jonathan P. Park ◽  
Arthur R. Brothman ◽  
Merlin G. Butler ◽  
Linda D. Cooley ◽  
Gordon W. Dewald ◽  
...  
Keyword(s):  
Turner Syndrome ◽  
Cell Lines ◽  
X Chromosome ◽  
Sex Chromosome ◽  
Chromosome Instability ◽  
Extensive Study ◽  
Small Ring ◽  
X Chromosomes ◽  
Cytogenetic Survey ◽  
N 93

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.

scholarly journals Severe haemophilia a in a preterm girl with turner syndrome - a case report from the prenatal period to early infancy (part I)

2020 ◽  
Vol 46 (1) ◽  
Author(s):  
Agnieszka Berendt ◽  
Monika Wójtowicz-Marzec ◽  
Barbara Wysokińska ◽  
Anna Kwaśniewska
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Turner Syndrome ◽  
X Chromosome ◽  
Diagnostic Procedures ◽  
Haemophilia A ◽  
Severe Haemophilia ◽  
Preterm Children ◽  
Initial Symptoms ◽  
The Central Nervous System

Abstract Background Bleedings are more frequent in the population of preterm children than among those born at term, much less in older children. The reasons for such bleedings in preterms include plasma factor deficiencies, immaturity of small vessels in the germinal matrix region, prenatal hypoxia or sepsis. They affect the brain tissue, the gastrointestinal tract and the respiratory system, or are manifested by prolonged bleedings from injection sites. Haemophilia is a rare cause of haemorrhages in the neonatal period, and in the female population it is even seen as an extremely rare disorder. Its aetiology in girls is diverse: inheriting defective genes from their parents, skewed X inactivation or a single X chromosome. Case presentation The article presents a case of a preterm girl born in the 28th week of pregnancy, who was diagnosed with severe haemophilia A stemming from the absence of the X chromosome. The girl’s father is healthy, but her mother’s brother suffers from haemophilia. On the second day of the child’s life, a prolonged bleeding from the injection site was observed. A coagulation profile revealed prolonged APTT which pointed to haemophilia A diagnosis. Moreover, a marked clinical dysmorphy, female sex and a negative family history on the father’s side led the treating team to extend the diagnostic procedures to encompass karyotype evaluation. The girl was diagnosed with Turner syndrome. No bleeding to the central nervous system was observed during her hospital stay. Conclusions Preterm children belong to the risk group of bleeding into the central nervous system or haemorrhages in the course of sepsis. Rare causes of such bleedings should also be borne in mind, including haemophilia. The initial symptoms of haemophilia in preterm children occur in the first days of their lives, which is connected with a number of invasive procedures required in that period. Genetic conditions may coexist with one another. Arriving at one diagnosis does not mean one should abandon further diagnostic procedures in cases where additional atypical symptoms are present which do not match the clinical image of a primary disease.

scholarly journals Differential activation of the hprt gene on the inactive X chromosome in primary and transformed Chinese hamster cells.

1989 ◽  
Vol 9 (4) ◽  
pp. 1635-1641 ◽  
Author(s):  
S G Grant ◽  
R G Worton
Keyword(s):  
Cell Lines ◽  
X Chromosome ◽  
Gene Activation ◽  
Chinese Hamster ◽  
Fibroblast Cell ◽  
Dna Demethylation ◽  
Hprt Gene ◽  
Primary Fibroblast ◽  
Chinese Hamster Cells ◽  
Inactive X Chromosome

We have investigated the genetic activation of the hprt (hypoxanthine-guanine phosphoribosyltransferase) gene located on the inactive X chromosome in primary and transformed female diploid Chinese hamster cells after treatment with the DNA methylation inhibitor 5-azacytidine (5azaCR). Mutants deficient in HPRT were first selected by growth in 6-thioguanine from two primary fibroblast cell lines and from transformed lines derived from them. These HPRT- mutants were then treated with 5azaCR and plated in HAT (hypoxanthine-methotrexate-thymidine) medium to select for cells that had reexpressed the hprt gene on the inactive X chromosome. Contrary to previous results with primary human cells, 5azaCR was effective in activating the hprt gene in primary Chinese hamster fibroblasts at a low but reproducible frequency of 2 x 10(-6) to 7 x 10(-6). In comparison, the frequency in independently derived transformed lines varied from 1 x 10(-5) to 5 x 10(-3), consistently higher than in the nontransformed cells. This increase remained significant when the difference in growth rates between the primary and transformed lines was taken into account. Treatment with 5azaCR was also found to induce transformation in the primary cell lines but at a low frequency of 4 x 10(-7) to 8 x 10(-7), inconsistent with a two-step model of transformation followed by gene activation to explain the derepression of hprt in primary cells. Thus, these results indicate that upon transformation, the hprt gene on the inactive Chinese hamster X chromosome is rendered more susceptible to action by 5azaCR, consistent with a generalized DNA demethylation associated with the transformation event or with an increase in the instability of an underlying primary mechanism of X inactivation.

scholarly journals Epistatic Control of Non-Mendelian Inheritance in Mouse Interspecific Crosses

Genetics ◽  
1996 ◽  
Vol 143 (4) ◽  
pp. 1739-1752 ◽  
Author(s):  
Xavier Montagutelli ◽  
Rowena Turner ◽  
Joseph H Nadeau
Keyword(s):  
X Chromosome ◽  
Genetic Basis ◽  
Mendelian Inheritance ◽  
The Other ◽  
Interspecific Crosses ◽  
Chromosome 2 ◽  
Mus Spretus ◽  
F1 Hybrid ◽  
Strong Deviation ◽  
Marker Loci

Abstract Strong deviation of allele frequencies from Mendelian inheritance favoring Mus spretus-derived alleles has been described previously for X-linked loci in four mouse interspecific crosses. We reanalyzed data for three of these crosses focusing on the location of the gene(s) controlling deviation on the X chromosome and the genetic basis for incomplete deviation. At least two loci control deviation on the X chromosome, one near Xist (the candidate gene controlling X inactivation) and the other more centromerically located. In all three crosses, strong epistasis was found between loci near Xist and marker loci on the central portion of chromosome 2. The mechanism for this deviation from Mendelian expectations is not yet known but it is probably based on lethality of embryos carrying particular combinations of alleles rather than true segregation distortion during oogenesis in F1 hybrid females.

scholarly journals The value of a simple method to decrease diagnostic errors in Turner syndrome: a case report

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Seyedetahere Mousavi ◽  
Batool Amiri ◽  
Saidee Beigi ◽  
Mohammadreza Farzaneh
Keyword(s):  
Case Report ◽  
Standard Deviation ◽  
Physical Examination ◽  
Turner Syndrome ◽  
X Chromosome ◽  
Genetic Disorder ◽  
Diagnostic Errors ◽  
Height Velocity ◽  
Target Height ◽  
Simple Method

Abstract Introduction Turner syndrome is a genetic disorder in females and is the result of complete or partial loss of an X chromosome during fertilization. The missing X chromosome is originally either from the mother's ovum or the father's sperm cell. Approximately 45% of patients have the 45,X karyotype and the rest have other variants of Turner syndrome, which are either mosaicism patterns or structural abnormalities of the X chromosome. Here, we report a case of Turner syndrome that is the fifth case of Turner syndrome with balanced Robertsonian translocation of (13;14)(q10;q10), and the sixth case with 44,X chromosomes, reported in the literature thus far. Case presentation A 10.3-year-old Persian girl was brought to our clinic by her parents, with the complaint of failure to thrive and short height. She had been examined and investigated by endocrinologists since the age of 4 years, but no definite diagnosis was made. At the time of presentation, she had been through three provocative growth hormone tests and had been on no medications for about a year. Her physical examination revealed mild retrognathia and micrognathia. Initially, she was started on somatropin treatment which, after 12 months, did not appropriately improve her height velocity. Therefore, a more thorough physical examination was performed, in which high arched palate and low posterior hairline were observed. There was also a difference between target height and patient height standard deviation scores. Karyotype study was requested, and Turner syndrome was confirmed. Conclusion The diagnosis of this case was not straightforward, both because the somatic presentations were not obvious, and because the physicians had not looked for them when performing the physical examinations. This case report introduces a rare 44,X chromosome karyotype of Turner syndrome and highlights the value in using the difference between target height and patient height standard deviation scores as a simple and inexpensive tool for diagnosis of this syndrome.

scholarly journals Clinical Significance of the Parental Origin of the X Chromosome in Turner Syndrome

2007 ◽  
Vol 92 (3) ◽  
pp. 846-852 ◽  
Author(s):  
Liora Sagi ◽  
Nehama Zuckerman-Levin ◽  
Aneta Gawlik ◽  
Lucia Ghizzoni ◽  
Atilla Buyukgebiz ◽  
...  
Keyword(s):  
Turner Syndrome ◽  
Clinical Significance ◽  
X Chromosome ◽  
Parental Origin

scholarly journals A Genetic Screen of the Drosophila X Chromosome for Mutations That Modify Deformed Function

Genetics ◽  
1998 ◽  
Vol 150 (4) ◽  
pp. 1497-1511 ◽  
Author(s):  
Brian Florence ◽  
William McGinnis
Keyword(s):  
Transcription Factor ◽  
Transcriptional Regulation ◽  
Cell Signaling ◽  
X Chromosome ◽  
Adaptor Protein ◽  
Genetic Screen ◽  
The Other ◽  
Homeotic Gene ◽  
Hox Proteins ◽  
Hox Gene

Abstract We have screened the Drosophila X chromosome for genes whose dosage affects the function of the homeotic gene Deformed. One of these genes, extradenticle, encodes a homeodomain transcription factor that heterodimerizes with Deformed and other homeotic Hox proteins. Mutations in the nejire gene, which encodes a transcriptional adaptor protein belonging to the CBP/p300 family, also interact with Deformed. The other previously characterized gene identified as a Deformed interactor is Notch, which encodes a transmembrane receptor. These three genes underscore the importance of transcriptional regulation and cell-cell signaling in Hox function. Four novel genes were also identified in the screen. One of these, rancor, is required for appropriate embryonic expression of Deformed and another homeotic gene, labial. Both Notch and nejire affect the function of another Hox gene, Ultrabithorax, indicating they may be required for homeotic activity in general.

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