Sexual and somatic determinants of the human Y chromosome: studies in a 46,XYp- phenotypic female.

A case of a 46,XYp- phenotypic female provided an opportunity to evaluate both sexual and somatic determinants for the Y chromosome. The patient had multiple stigmata of Turner syndrome, but normal stature. Laparotomy revealed a normal uterus and tubes, with 1.5 cm undifferentiated gonads. Serological tests for H-Y antigen (ostensibly the product of Y-chromosomal testis-determining genes) indicated absence of the H-Y+ phenotype normally associated with the intact Y chromosome. We conclude that genes exist on the short arm of the human Y chromosome which both suppress some of the somatic stigmata of Turner syndrome and determine normal expression of H-Y antigen and testicular differentiation of the primitive gonad. Our data are consistent with the view that H-Y genes comprise a family of testis-determinants, and that loss of a critical moiety is inconsistent with normal development of the male gonad.     

Chromosome 13 long arm interstitial deletion associated with features of Noonan phenotype

A 22-year-old Caucasian mildly retarded male presented with facial features of high nasal bridge, prominent supraorbital ridges, some malar hypoplasia, prognathism, short philtrum, and prominent full lips associated with shortness of stature, nuchal webbing, and esotropia. His cardiac exam and genital development were normal. The diagnosis of Noonan syndrome had been previously entertained. A chromosome analysis revealed an interstitial deletion of a chromosome 13 at (q21.32q22.3).     

Turner syndrome and female sex chromosome aberrations: deduction of the principal factors involved in the development of clinical features

Although clinical features in Turner syndrome have been well defined, underlying genetic factors have not been clarified. To deduce the factors leading to the development of clinical features, we took the following four steps: (1) assessment of clinical features in classic 45,X Turner syndrome; (2) review of clinical features in various female sex chromosome aberrations (karyotype-phenotype correlations); (3) assessment of factors that could lead to Turner features; and (4) correlation of the clinical features with the effects of specific factors. The results indicate that the clinical features in 45,X and in other female sex chromosome aberrations may primarily be determined by: (1) degree of global non-specific developmental defects caused by quantitative alteration of a euchromatic or noninactivated region; (2) dosage effect of a pseudoautosomal growth gene(s), a Y-specific growth gene(s), and an Xp-Yp homologous lymphogenic gene(s); and (3) degree of chromosome pairing failure in meiocytes that are destined to develop as oocytes in the absence of SRY.     

Genetische Prädisposition für Wilms-Tumor

Wilms tumor (WT) is an embryonal tumor of the kidney and is due to aberrant proliferation of early precursor cells. WT1 mutations are found in 10–15% of WT. The WT1 gene has a function during normal kidney and genital development. Germline mutations in this gene are found in patients with urogenital abnormalities, isolated nephrotic syndrome, Denys Drash syndrome, Frasier syndrome, WAGR syndrome (Wilms tumor, aniridia, genital malformation, and mental retardation), and some rare cases of familial WT. These patients are at high risk of unilateral WT, and also of synchronous or metachronous bilateral WT, which may occur later in life. An elevated risk of WT is also observed in some overgrowth syndromes, various tumor predisposition syndromes, and specific constitutional aneuploidies. Embryonal tumors develop during early phases of development when cells still have a high doubling rate. Aberrations that delay or inhibit the switch from proliferation to differentiation lead to an expanded cell pool, in which further mutations can occur in various genes that regulate this process. This may explain the heterogeneous diseases/genetic aberrations that are associated with an elevated risk of WT.     

The uterine length in women with Turner syndrome reflects the postmenarcheal daily estrogen dose

AIM: To evaluate the effects of estrogen substitution on the uterine development in patients with Turner syndrome. METHOD: 57 women, aged 18.1-41.5 years, were treated with estrogen from puberty induction. RESULTS: In 21 women (37%), the uterus developed to >65 mm in length. The daily estrogen dose correlated with both uterine length (r = 0.29; p < 0.05) and Tanner breast stage (r = 0.44; p < 0.001). A negative correlation between age at artificial menarche and uterine length was found (r = -0.29; p < 0.05). The endometrium thickness was greater in women with an uterus length >65 mm (p < 0.05). In 50% of the women (18 were evaluated), an adult-shaped uterus developed. Previous growth hormone therapy (n = 32) had no impact on the uterus length. CONCLUSIONS: The uterine development was suboptimal in most patients. Further investigation is needed to optimize estrogen therapy for uterine development in patients with Turner syndrome.     

Ovarian development in 46,XY gonadal dysgenesis

Summary In human the XY ovary is degenerative, there being scant evidence of persistence of that organ beyond the perinatal period. Here we describe indications of functional ovarian tissue in a 17-year-old female with male karyotype, H-Y⁺ cellular phenotype, and some signs of the Turner syndrome. Her gonads were removed after the onset of secondary amenorrhea. Histological examination revealed a degenerative right ovary devoid of germ cells and follicles, and a left streak gonad. There was no trace of testicular development in either side.     

Radiological signs of Leri-Weill dyschondrosteosis in Turner syndrome

BACKGROUND/AIMS: Leri-Weill dyschondrosteosis (LWD), a mesomelic short stature syndrome with Madelung deformity, was recently reported to be caused by SHOX (short stature homeobox-containing gene) haploinsufficiency. The loss of SHOX on Xp22.32, also called PHOG (pseudoautosomal homeobox-containing osteogenic gene), through structural aberrations of the X chromosome was also implicated in the short stature phenotype and some additional stigmata of Turner syndrome. The aim of this study was to systematically examine left-hand radiographs from Turner girls for the presence of signs of LWD. METHODS: We retrospectively studied 168 left-hand radiographs from 54 patients with Turner syndrome (bone age >10.5 years) who were treated with rhGH and seen during the last 10 years in our clinic. For comparison, we analyzed 7 radiographs from 5 patients with LWD and 52 radiographs from 20 patients with GH deficiency. The shape of the distal radial epiphysis (triangularisation index = TI) and the carpal angle were quantitatively measured. In addition, we screened for the presence of a premature cleft fusion or an ulnar deviation of the articular surface of the distal radial epiphysis and for fourth metacarpal shortening. One of 54 Turner girls (2%) was affected with LWD and presented with Madelung deformity. RESULTS: No milder forms of Madelung deformity were detected. However, there was a significant trend to a triangular shape of the distal radial epiphysis in Turner syndrome: the median TI was 2.7 in normal controls (range 1.8-3.7), 3.1 in Turner girls (range 2.0-6.3) (p < 0.001 against controls), and 6.0 in patients with LWD (range 3.5-11.0) (p < 0.001 against controls). CONCLUSIONS: The triangularisation index did not correlate with the carpal angle (median 122.5 Copyright 2001 S. Karger AG, Basel     

Dermatoglyphics in turner syndrome

Finger and Palmar dermatoglyphics in 25 karyotypically proven cases of Turner syndrome representing Northwestern region of India are presented and compared with those obtained on their 102 normal female counterparts. Predominance of ulnar loops over other patterns was recorded in turner patients. Mean total finger ridge count in Turner syndrome (147.4) remained higher than the normal females (121.1). c-d interdigital ridge count in turners remained significantly (p≤0.05) higher than their normal female counter-parts. In contrast to their western counterparts distal placement of axial triradius in both the palms of none of the Turner syndrome patients representing the current series was recorded. Occurrence of whorls and arches in hypothenar region of 12% and 4% was respectively noticed in right palm of patients. The use of distinctive dermatoglyphic features recorded amongst Turner syndrome patients representing this study may be made to corroborate diagnosis of this entity in settings where facilities to carry out karyotyping do not exist.     

Portal vein thrombosis and high factor VIII in Turner syndrome

BACKGROUNDS/AIMS: Turner syndrome is not usually associated with thrombotic events. The aim of this study is to report 3 Turner syndrome patients with portal vein thrombosis and, in 2 of them, high factor VIII. These findings are compared to values in Turner syndrome patients without thrombosis and controls. METHODS: In different years, 3 patients with Turner syndrome were initially seen at the Gastroenterology Clinic of Hospital de Clínicas de Porto Alegre, Brazil, for portal vein thrombosis. After the most common causes of portal vein thrombosis and thrombophilias had been excluded, the 2 surviving patients were studied for clotting factors VIII, IX and von Willebrand factor. The same factors were also assessed in 25 Turner syndrome patients without thrombosis and 25 normal girls. RESULTS: One of the patients with portal vein thrombosis died before the study. In the 2 surviving patients, factors VIII and von Willebrand levels were >150 IU/dl, which is considered to be high. In Turner syndrome patients without thrombosis, the mean factor VIII level was 127.2 +/- 41.1 IU/dl and for von Willebrand factor 101.2 +/- 26.9 IU/dl, while in control girls these were 116.0 +/- 27.6 and 94.28 +/- 27.5 IU/dl, respectively. Factor VIII and von Willebrand factor were not different between these 2 groups. When non-O blood group Turner syndrome patients and normal girls were compared, the former had significantly higher levels of factor VIII. CONCLUSIONS: This is the first report on the unusual finding of portal thrombosis in patients with Turner syndrome in whom high levels of factor VIII and von Willebrand factor were found. Factor VIII is higher in the non-O blood group Turner syndrome patients without thrombosis when compared to normal girls.     

Gradual acquisition of the developmental capacity to differentiate adult structures by the genital disc of Drosophila melanogaster

Summary Diplo-X flies homozygous for the transform-er-2 ^ts (tra-2 ^ts) mutation develop into females at 16° C, while they develop into males at 29° C (Belote and Baker 1982). By means of this conditional mutation, we have carried out a detailed analysis of the development of the genital disc. Temperature shifts between 16 and 29° C, in both directions, and temperature pulses at 29° C, have been applied during the larval growth of tra-2 ^ts homozygous diplo-X flies, and the external derivatives of the genital disc have been analysed. Genital discs shifted from 16 to 29° C rapidly lose their capacity to differentiate female genital structures, while they become able to differentiate male genital structures whose inventory is more complete the earlier in larval development the temperature shift is carried out; moreover, duplicated male genital structures were observed. In the shift from 29 to 16° C, the genital disc loses its capacity to differentiate male genital structures, while it becomes able to differentiate female genital structures. The inventory of male structures is smaller, and the inventory of the female structures is more complete, the earlier in larval development the temperature is shifted. No duplicated female or male genital structures were observed in the downshift experiment. With respect to the analia, the shift from 16 to 29° C resulted in the quick formation of pure male anal plates, while in the opposite shift the formation of pure female anal plates occurred gradually. Moreover, the time course for the dorsal and ventral anal plates to show normal female phenotype was different: when the dorsal anal plates were completely normal, it was still possible to find incomplete ventral anal plates. In the pulse experiment at 29° C, the genital disc is able to differentiate both female and male genital structures, although the inventory of the latter ones was not complete. In addition, the capacity of the genital disc to differentiate male genital structures depended on the duration of the temperature pulse. The anal plates were always female, although they showed a reduction in their size, the ventral female anal plate being more affected than the dorsal one. No male anal plates were observed. The results have revealed that the genital disc follows a sequence in its capacity to differentiate female or male adult structures. We suggest that this sequence reflects the sequence of determination events occurring in the genital disc during its larval growth. In addition, results shown here provide evidence for the existence in the female genital primordium of a set of cells capable of giving rise either to female genital structures (ventral vaginal plates) or to male genital structures (hypandrium and penis apparatus). We also present evidence supporting the previous idea of two primordia for the anal plates.     

Ganglioneuroma Manifesting as an Incidental Adrenal Mass in an Adult With Turner’s Syndrome

ObjectiveTo report a case of ganglioneuroma masquerading as an incidental adrenal mass in an adult patient with Turner’s syndrome.MethodsWe present the clinical, laboratory, radiologic, and pathologic findings in this patient.ResultsA 31-year-old woman with Turner’s syndrome who had previously been treated with growth hormone replacement had an incidentally discovered mass, apparently arising from the left adrenal gland. The mass was “silent” clinically and biochemically, but imaging characteristics were not reassuring for a benign cortical adenoma. Because of uncertainty regarding the nature of the mass, it was removed laparoscopically; during this procedure, it was noted to be intimately associated with, but anatomically distinct from, the left adrenal gland. The pathology report confirmed the presence of a benign ganglioneuroma.Conclusion: Although ganglioneuroma has previously been noted to be associated with Turner’s syndrome (especially in pediatric patients), to the best of our knowledge this is the first report of a ganglioneuroma manifesting as an incidental adrenal mass in an adult patient with Turner’s syndrome. (Endocr Pract. 2005;11:382-384)     

Evidence for a Turner syndrome locus or loci at Xp11.2-p22.1.

Turner syndrome is the complex human phenotype associated with complete or partial monosomy X. Principle features of Turner syndrome include short stature, ovarian failure, and a variety of other anatomic and physiological abnormalities, such as webbed neck, lymphedema, cardiovascular and renal anomalies, hypertension, and autoimmune thyroid disease. We studied 28 apparently nonmosaic subjects with partial deletions of Xp, in order to map loci responsible for various components of the Turner syndrome phenotype. Subjects were carefully evaluated for the presence or absence of Turner syndrome features, and their deletions were mapped by FISH with a panel of Xp markers. Using a statistical method to examine genotype/phenotype correlations, we mapped one or more Turner syndrome traits to a critical region in Xp11.2-p22.1. These traits included short stature, ovarian failure, high-arched palate, and autoimmune thyroid disease. The results are useful for genetic counseling of individuals with partial monosomy X. Study of additional subjects should refine the localization of Turner syndrome loci and provide a rational basis for exploration of candidate genes.     

Turner syndrome morphology and morphometrics: Cardiac hypoplasia as a cause of midgestation death

BACKGROUND: A female fetus with massive truncal-limb hydrops and large, loculated, nuchal hygromas in midgestation is highly likely to have Turner syndrome. This phenotype is recognized to be usually lethal, with only more mildly affected fetuses surviving to term birth. METHODS: The morphology and morphometrics of 117 midgestation fetuses with phenotypic Turner syndrome were analyzed. RESULTS: More than 90% of fetuses with phenotypic Turner syndrome were found to have heart weights below the 2.5 centile, as well as lung hypoplasia and restricted limb growth for brain weight standards, although brain weight was only mildly reduced for gestational age. In contrast, subnormal heart weight was much less common among fetuses with other etiologies of hydrops, hygromas, or pleural effusions. CONCLUSIONS: We hypothesize that myocardial hypoplasia is a primary defect in Turner syndrome, and it leads to or is a major contributor to the phenotypic features that end in midgestational death.     

The various phenotypes in Xp deletion. Observations in eleven patients

Summary Eleven Xp-deletion patients with various phenotypes ranging from normal to the Turner syndrome are reported. To explain the phenotypy-karyotype correlation the hypothesis is brought forward that (an) autosomal gene(s) may play a role in the pathogenesis of the Turner syndrome.     

X chromosome inactivation and micronuclei in normal and Turner individuals

Studies on aneuploidy have shown that the X is the most frequently lost chromosome in females, and that the number of X chromosome-positive micronuclei increases with age in women. Recently, we showed that the inactive X chromosome is incorporated preferentially in micronuclei. The objectives of the current study were, firstly, to determine the incidence of X chromosome incorporation into micronuclei in males and, secondly, to determine the incidence of X chromosome incorporation into micronuclei of females with Turner syndrome. Blood samples were obtained from 18 male newborns and 35 normal adult males ranging in age from 22 to 79 years and from seven women with non-mosaic Turner syndrome aged 11–39 years. Isolated lymphocytes were cultured in the presence of cytochalasin B and 2000 binucleated cells per subject were scored for micronuclei. Cells were then hybridized with the biotinylated X centromere-specific probe, pBamX7, and visualized with fluorescein-conjugated avidin. All micronucleated cells were relocated and evaluated for the presence or absence of the X chromosome. Of the 335 micronuclei observed, 6.6% (22/335) contained an X chromosome. Analysis of variance shows a statistically significant increase, for both males and Turner females, in the number of X chromosome-positive micronuclei with age (P < 0.001). These data also show that the X chromosome is included in micronuclei from males more often than would be expected by chance (P < 0.005; χ² analysis, 15 df). Here we show that there is a tenfold difference in the frequency of X chromosome-positive micronuclei in 46,XX females compared to 46,XY males and 45,X females, providing further support to our previous finding that the X chromosome in micronuclei is the inactive chromosome. Received: 29 April 1997 / Accepted: 9 May 1997     

Deletion of the proximal long arm of chromosome 3 in an infant with features of Turner syndrome

A case of deletion of the proximal one-fourth of chromosome 3 long arm is described. While the Turner syndrome phenotype was present neonatally, the patient has no structural or numerical abnormality of the sex chromosomes, and thus may represent an autosomal deletion with a clinical picture similar to Turner syndrome. Her score on the Noonan syndrome index of Duncan et al. (1981) is 27%, making Noonan syndrome unlikely.     

Requirement ofwingless signaling andengrailed action in the development and differentiation of reproductive system inDrosophila

The segment polarity geneswingless (wg) andengrailed (en) have been shown to play important roles in pattern formation at different stages ofDrosophila development in the thoracic imaginai discs. We have studied the patterns of expression of these genes in genital discs from wild type larvae, pupae and pharate adults and also from hetero-allelic mutant combinations of these genes. Our results suggest that these genes play vital roles in the normal development and differentiation of genital discs and gonads. In the absence of normalwg oren functions, the flies showed a complete lack of internal accessory reproductive organs and specific defects in the external genitalia. In addition, the testes in such males were small, rounded and with an abnormal cellular organization, although the ovaries in females appeared normal. Temperature shift experiments using the conditional mutant allele ofwg, (wg ^IL-114 ) indicated a requirement ofwg signaling from second instar onwards for normal development and differentiation of the accessory reproductive organs. Using a heat-shock allele (Hs-wg) we also show that the spatially regulated expression ofwg as a pre-requisite for normal development and differentiation. Based on the expression patterns ofen andhedgehog (hh) we suggest that even in the genital disc development and differentiation the action ofen is mediated throughhh.     

The role of the transformer genes in the development of genitalia and analia of Drosophila melanogaster

The autosomal mutations transformer (tra) and transformer-2 (tra-2) of Drosophila convert chromosomal females (X/X) into phenotypical males. Our analysis aims at an understanding of the role which the transformer genes play in the development of the sexually dimorphic genital disc. In each Drosophila embryo, this disc starts development with a male and a female genital primordium, and an anal primordium. Our experiments involved the production of cell clones that were made homozygous for tra or tra-2 at different times of development. Homozygous clones were obtained by inducing mitotic recombination in three types of females heterozygous for tra or tra-2. The cells of the homozygous tra/tra or tra-2/tra-2 clones responded by changing from the female into the male pathway. Male genital structures developed if the clones were induced not later than 81 hr into development. In the analia, male clones appeared up to 120 hr. Our results show that the action of the wild-type alleles of tra⁺ and tra-2⁺ is required until late in larval development to repress the male genital primordium and to support development of the female primordium, as well as to maintain the anal primordium in the female pathway. Our data also suggest that the embryonic genital disc consists of two compartments, one containing the precursors for penis and analia, the other those of the male and female genitalia.     

The proportion of cells with functional X disomy is associated with the severity of mental retardation in mosaic ring X Turner syndrome females

Turner syndrome females (45,X) do not have mental retardation (MR), whereas some mosaic ring X Turner syndrome females, with 45,X/46,X,r(X), have severe MR. The MR is believed to be caused by a failure of X chromosome inactivation (XCI) of the small ring X chromosome, which leads to functional X disomy (FXD), To explore this hypothesis, we examined the proportion of FXD cells in the peripheral blood of four ring X Turner syndrome females with various levels of MR, using two newly developed XCI assays based on DNA methylation of X-linked genes. As a result, the two patients with extremely severe MR showed complete FXD patterns, whereas the remaining two patients with relatively milder MR showed partial FXD patterns. These results indicate that the proportion of FXD cells may be associated with the severity of MR in mosaic ring X Turner syndrome females, although this association should be confirmed by examining brain cells during development. One of the cases with severe MR and a complete FXD pattern neither lacked the XIST gene nor had uniparental X isodisomy, and we discuss the mechanism of the failure of XCI in this case.