Turner's syndrome

Early Bilateral Gonadoblastoma in a Young Child with Mosaicism for Turner Syndrome and Trisomy 18 with Y Chromosome

Mosaic Turner syndrome (TSM) commonly occurs in the form of 45,X/46,XX and 45,X/46,X,i(X)(q10). Mosaicism for a Y chromosome, 45,X/46,XY, has been well documented and is associated with increased risk of gonadoblastoma (GB). To date, there are only six reported cases of TSM with a trisomy 18 karyotype, and only two of these were phenotypically female with 45,X/47,XY,+18 karyotype. We present the case of a phenotypically female infant born with dysmorphic features. G-banded karyotype and interphase FISH of blood showed 45,X in 95% and 47,XY,+18 (trisomy 18) in 5% of cells analysed. However, interphase FISH of buccal cells showed only the presence of the 45,X cell line. Due to the presence of Y chromosome material, elective gonadectomy was performed at 13 months of age. There were bilateral streak ovaries with early evidence of GB bilaterally, a rudimentary uterus and bilateral fallopian tubes with unilateral ectopic adrenal tissue identified histologically. Interphase FISH of the gonadal tissue was similar to the blood findings with 45,X in 86% of cells and 47,XY,+18 in 14% of cells analysed. This case highlights a rare karyotype of TSM and trisomy 18 in the same patient and is the first reporting the associated finding of bilateral GB.

Genomics-based non-invasive prenatal testing for detection of fetal chromosomal aneuploidy in pregnant women

BACKGROUND

Common fetal aneuploidies include Down syndrome (trisomy 21 or T21), Edward syndrome (trisomy 18 or T18), Patau syndrome (trisomy 13 or T13), Turner syndrome (45,X), Klinefelter syndrome (47,XXY), Triple X syndrome (47,XXX) and 47,XYY syndrome (47,XYY). Prenatal screening for fetal aneuploidies is standard care in many countries, but current biochemical and ultrasound tests have high false negative and false positive rates. The discovery of fetal circulating cell-free DNA (ccfDNA) in maternal blood offers the potential for genomics-based non-invasive prenatal testing (gNIPT) as a more accurate screening method. Two approaches used for gNIPT are massively parallel shotgun sequencing (MPSS) and targeted massively parallel sequencing (TMPS).

OBJECTIVES

To evaluate and compare the diagnostic accuracy of MPSS and TMPS for gNIPT as a first-tier test in unselected populations of pregnant women undergoing aneuploidy screening or as a second-tier test in pregnant women considered to be high risk after first-tier screening for common fetal aneuploidies. The gNIPT results were confirmed by a reference standard such as fetal karyotype or neonatal clinical examination.

SEARCH METHODS

We searched 13 databases (including MEDLINE, Embase and Web of Science) from 1 January 2007 to 12 July 2016 without any language, search filter or publication type restrictions. We also screened reference lists of relevant full-text articles, websites of private prenatal diagnosis companies and conference abstracts.

SELECTION CRITERIA

Studies could include pregnant women of any age, ethnicity and gestational age with singleton or multifetal pregnancy. The women must have had a screening test for fetal aneuploidy by MPSS or TMPS and a reference standard such as fetal karyotype or medical records from birth.

DATA COLLECTION AND ANALYSIS

Two review authors independently carried out study selection, data extraction and quality assessment (using the QUADAS-2 tool). Where possible, hierarchical models or simpler alternatives were used for meta-analysis.

MAIN RESULTS

Sixty-five studies of 86,139 pregnant women (3141 aneuploids and 82,998 euploids) were included. No study was judged to be at low risk of bias across the four domains of the QUADAS-2 tool but applicability concerns were generally low. Of the 65 studies, 42 enrolled pregnant women at high risk, five recruited an unselected population and 18 recruited cohorts with a mix of prior risk of fetal aneuploidy. Among the 65 studies, 44 evaluated MPSS and 21 evaluated TMPS; of these, five studies also compared gNIPT with a traditional screening test (biochemical, ultrasound or both). Forty-six out of 65 studies (71%) reported gNIPT assay failure rate, which ranged between 0% and 25% for MPSS, and between 0.8% and 7.5% for TMPS.In the population of unselected pregnant women, MPSS was evaluated by only one study; the study assessed T21, T18 and T13. TMPS was assessed for T21 in four studies involving unselected cohorts; three of the studies also assessed T18 and 13. In pooled analyses (88 T21 cases, 22 T18 cases, eight T13 cases and 20,649 unaffected pregnancies (non T21, T18 and T13)), the clinical sensitivity (95% confidence interval (CI)) of TMPS was 99.2% (78.2% to 100%), 90.9% (70.0% to 97.7%) and 65.1% (9.16% to 97.2%) for T21, T18 and T13, respectively. The corresponding clinical specificity was above 99.9% for T21, T18 and T13.In high-risk populations, MPSS was assessed for T21, T18, T13 and 45,X in 30, 28, 20 and 12 studies, respectively. In pooled analyses (1048 T21 cases, 332 T18 cases, 128 T13 cases and 15,797 unaffected pregnancies), the clinical sensitivity (95% confidence interval (CI)) of MPSS was 99.7% (98.0% to 100%), 97.8% (92.5% to 99.4%), 95.8% (86.1% to 98.9%) and 91.7% (78.3% to 97.1%) for T21, T18, T13 and 45,X, respectively. The corresponding clinical specificities (95% CI) were 99.9% (99.8% to 100%), 99.9% (99.8% to 100%), 99.8% (99.8% to 99.9%) and 99.6% (98.9% to 99.8%). In this risk group, TMPS was assessed for T21, T18, T13 and 45,X in six, five, two and four studies. In pooled analyses (246 T21 cases, 112 T18 cases, 20 T13 cases and 4282 unaffected pregnancies), the clinical sensitivity (95% CI) of TMPS was 99.2% (96.8% to 99.8%), 98.2% (93.1% to 99.6%), 100% (83.9% to 100%) and 92.4% (84.1% to 96.5%) for T21, T18, T13 and 45,X respectively. The clinical specificities were above 100% for T21, T18 and T13 and 99.8% (98.3% to 100%) for 45,X. Indirect comparisons of MPSS and TMPS for T21, T18 and 45,X showed no statistical difference in clinical sensitivity, clinical specificity or both. Due to limited data, comparative meta-analysis of MPSS and TMPS was not possible for T13.We were unable to perform meta-analyses of gNIPT for 47,XXX, 47,XXY and 47,XYY because there were very few or no studies in one or more risk groups.

AUTHORS' CONCLUSIONS

These results show that MPSS and TMPS perform similarly in terms of clinical sensitivity and specificity for the detection of fetal T31, T18, T13 and sex chromosome aneuploidy (SCA). However, no study compared the two approaches head-to-head in the same cohort of patients. The accuracy of gNIPT as a prenatal screening test has been mainly evaluated as a second-tier screening test to identify pregnancies at very low risk of fetal aneuploidies (T21, T18 and T13), thus avoiding invasive procedures. Genomics-based non-invasive prenatal testing methods appear to be sensitive and highly specific for detection of fetal trisomies 21, 18 and 13 in high-risk populations. There is paucity of data on the accuracy of gNIPT as a first-tier aneuploidy screening test in a population of unselected pregnant women. With respect to the replacement of invasive tests, the performance of gNIPT observed in this review is not sufficient to replace current invasive diagnostic tests.We conclude that given the current data on the performance of gNIPT, invasive fetal karyotyping is still the required diagnostic approach to confirm the presence of a chromosomal abnormality prior to making irreversible decisions relative to the pregnancy outcome. However, most of the gNIPT studies were prone to bias, especially in terms of the selection of participants.

The Turner syndrome life course project: Karyotype-phenotype analyses across the lifespan

INTRODUCTION

Turner syndrome (TS) is associated with a variety of morbidities affecting nearly every body system, some of which increase in prevalence in adult life. The severity of clinical features in TS is roughly in parallel with the magnitude of the deficit of X-chromosome material. The aim of this study was to extend the established karyotype-phenotype relationships using data from a large adult cohort.

MATERIALS AND METHODS

Karyotypes were available in 656 women with TS. 611 of whom could be classified into five major groups within the cohort: 45,X; 45,X mosaicism (45,X/46,XX); isochromosome X (isochromosome Xq); mosaicism 45,X/46,XY and ring X. Continuous variables such as blood pressure and biochemical markers from clinic data were binarised allocating those in the upper quartile to represent at-risk individuals. With the exception of bone mineral density T-score for which the lower quartile was allocated as at risk. For comorbidities, initiation of formal treatment was recorded.

RESULTS

45,X/46,XX had considerably lower frequency of comorbidities compared to 45,X. The isochromosome group experienced similar outcomes to 45,X. Novel associations were found between the XY mosaic karyotype group and a decreased prevalence of thyroid disease and severe hearing loss. A previously unreported increased incidence of metabolic syndrome was noted within the ring chromosome subgroup.

CONCLUSIONS

Karyotype may play an important factor against stratifying risk of comorbidity in TS and should be taken into consideration when managing adults with TS. Further investigations of the isochromosome (Xq) and ring groups are necessary to further clarify their associations with comorbidities.

Turner syndrome caused by rare complex structural abnormalities involving chromosome X

Turner syndrome (TS) is a phenotypic heterogeneous genetic disorder caused by the loss of an X-chromosome or X-structural abnormalities in the X-chromosome, and affects approximately 1 in every 2,500 females. The affected individuals may develop diverse clinical features, including short stature, ovarian dysgenesis, skeletal dysplasia, facial abnormalities and other disorders. A constitutional karyotype of 45, X accounts for nearly 50% of TS patients, while X-mosaicism and other X-chromosomal structural abnormalities, including deletions, duplications, ring, isodicentric chromosomes, inversions and translocations, have been reported in other cases. The present study reports the results of chromosome microarray analysis (CMA) in two Chinese female TS patients with idiosyncratic karyotypes. The first patient had a karyotype of 46, X, der(X), and the CMA results demonstrated that the derivative chromosome was an abnormal X-chromosome that consisted of three deletions (Xp21.3-p11.23, Xp11.1-q13.1 and Xq21.31-q28), as well as three duplications (Xp22.33-p21.3, Xp11.23-p11.1 and Xq13.1-q21.31). The karyotype of the second patient was 46, X, der(X) t(X;?)(q 22.1;?),inv(11)(q13.5q21), while CMA revealed an Xq21.2-q27.1 duplication and an Xq27.2-q28 deletion. In conclusion, the current study performed genotype-phenotype correlation analysis in two patients and provided novel insight of the genotype of TS.

Clinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting

Turner syndrome affects 25-50 per 100,000 females and can involve multiple organs through all stages of life, necessitating multidisciplinary approach to care. Previous guidelines have highlighted this, but numerous important advances have been noted recently. These advances cover all specialty fields involved in the care of girls and women with TS. This paper is based on an international effort that started with exploratory meetings in 2014 in both Europe and the USA, and culminated with a Consensus Meeting held in Cincinnati, Ohio, USA in July 2016. Prior to this meeting, five groups each addressed important areas in TS care: 1) diagnostic and genetic issues, 2) growth and development during childhood and adolescence, 3) congenital and acquired cardiovascular disease, 4) transition and adult care, and 5) other comorbidities and neurocognitive issues. These groups produced proposals for the present guidelines. Additionally, four pertinent questions were submitted for formal GRADE (Grading of Recommendations, Assessment, Development and Evaluation) evaluation with a separate systematic review of the literature. These four questions related to the efficacy and most optimal treatment of short stature, infertility, hypertension, and hormonal replacement therapy. The guidelines project was initiated by the European Society for Endocrinology and the Pediatric Endocrine Society, in collaboration with The European Society for Pediatric Endocrinology, The Endocrine Society, European Society of Human Reproduction and Embryology, The American Heart Association, The Society for Endocrinology, and the European Society of Cardiology. The guideline has been formally endorsed by the European Society for Endocrinology, the Pediatric Endocrine Society, the European Society for Pediatric Endocrinology, the European Society of Human Reproduction and Embryology and the Endocrine Society. Advocacy groups appointed representatives who participated in pre-meeting discussions and in the consensus meeting.

Overlapping genetic pathways in the skeletal dysplasias of a middle woodland individual: A case study

Studies of interacting/overlapping genetic skeletal disorders are rare for populations today, but even more so for archaeological contexts. The skeletal remains of an adult female (EZ 3-7-1) were excavated in the 1980s from the Middle Woodland (50BC-AD400) context of the Elizabeth site (11PK512) in the lower Illinois Valley (LIV), USA. Reported here are the standard score (z-score) comparisons of the measured skeletal differences of EZ 3-7-1 with a reference sample and a re-analysis of the individual's pathological changes, with special consideration placed on refining the disease diagnosis. The impressive preservation and meticulous recovery of these skeletal remains have provided the opportunity to identify the first and earliest archaeological example of an individual (EZ 3-7-1) with a combined genetic skeletal dysplasia, Leri-Weill dyschondrosteosis and achondroplasia.

First Report of Two Rare Entities in a Family: 49,XXXXY and 45,X

49,XXXXY and 45,X syndromes are sex chromosome aneuploidies in which the affected individuals present with hypergonadotropic hypogonadism, short or long stature, and skeletal malformations. Psychological, endocrinological, and orthopaedic disorders constitute the major problems in the clinical follow-up. We report a family with two rare entities: 49,XXXXY and 45, X. Sex chromosome abnormalities should especially be in mind in the evaluation of patients with micropenis, mental retardation, and hypergonadotropic hypogonadism. Management mandates a multidisciplinary approach with pediatric endocrinology, pediatric surgery, orthopaedics, psychiatry, and clinical genetic evaluations. To our knowledge, our cases are the first to report the sibling patients with 49,XXXXY and 45,X.

Can Brain Natriuretic Peptides and Osteoprotegerin Serve As Biochemical Markers for the Detection of Aortic Pathology in Children and Adolescents with Turner Syndrome?

Turner syndrome (TS) is a chromosomal disorder that affects 1:2,000 females. It results from either the complete or partial loss of the X chromosome as well as other aberrations. Clinical features of TS include short stature, delayed puberty, and congenital cardiac malformations. TS children also have an increased prevalence of cardiometabolic risk factors, which predisposes them to complications like coronary artery disease, cerebrovascular-related deaths, and aortic dissection. Early cardiac imaging, such as echocardiography and cardiac magnetic resonance imaging, are recommended to detect underlying aortic pathology. However, these modalities are limited by cost, accessibility, and are operator dependent. In view of these shortcomings, alternative methods, like vascular biomarkers, are currently being explored. There are only a few studies that have examined the relationship between B-type natriuretic peptide (BNP), N-terminal pro BNP (NT pro-BNP), and osteoprotegerin (OPG) and aortic disease in TS, and thus the data are only in proof-of-concept stages. Further meticulous longitudinal studies are required before BNP, NT pro-BNP, and OPG are used as vascular biomarkers for the detection of aortic disease in childhood and adolescent TS.

A complete duplication of X chromosome resulting in a tricentric isochromosome originated by centromere repositioning

BACKGROUND

Neocentromeres are rare and considered chromosomal aberrations, because a non-centromeric region evolves in an active centromere by mutation. The literature reported several structural anomalies of X chromosome and they influence the female reproductive capacity or are associated to Turner syndrome in the presence of monosomy X cell line.

CASE PRESENTATION

We report a case of chromosome X complex rearrangement found in a prenatal diagnosis. The fetal karyotype showed a mosaicism with a 45,X cell line and a 46 chromosomes second line with a big marker, instead of a sex chromosome. The marker morphology and fluorescence in situ hybridization (FISH) characterization allowed us to identify a tricentric X chromosome constituted by two complete X chromosome fused at the p arms telomere and an active neocentromere in the middle, at the union of the two Xp arms, where usually are the telomeric regions. FISH also showed the presence of a paracentric inversion of both Xp arms. Furthermore, fragility figures were found in 56% of metaphases from peripheral blood lymphocytes culture at birth: a shorter marker chromosome and an apparently acentric fragment frequently lost.

CONCLUSIONS

At our knowledge, this is the first isochromosome of an entire non-acrocentric chromosome. The neocentromere is constituted by canonical sequences but localized in an unusual position and the original centromeres are inactivated. We speculated that marker chromosome was the result of a double rearrangement: firstly, a paracentric inversion which involved the Xp arm, shifting a part of the centromere at the p end and subsequently a duplication of the entire X chromosome, which gave rise to an isochromosome. It is possible to suppose that the first event could be a result of a non-allelic homologous recombination mediated by inverted low-copy repeats. As expected, our case shows a Turner phenotype with mild facial features and no major skeletal deformity, normal psychomotor development and a spontaneous development of puberty and menarche, although with irregular menses since the last follow-up.

Disorders of Sexual Development in Adult Women

Disorders (differences) of sexual development encompass a variety of conditions with atypical development of chromosomal, gonadal, or anatomic sex. Three of the most common differences of sex development conditions include congenital adrenal hyperplasia, complete androgen insensitivity, and Turner syndrome. Obstetrician-gynecologists who care for affected individuals in their practice must be familiar with the genetic, endocrine, and anatomic considerations of the most common conditions to provide optimal care. As women with these conditions transition to adult care, the gynecologist needs to assess the patient's understanding and educate her regarding her diagnosis and ongoing medical care. All of these conditions may affect self-perception, mental health, fertility, sexual function, and bone and cardiovascular health. Women with congenital adrenal hyperplasia need lifelong endocrine management and require genetic counseling before pregnancy. Women with androgen insensitivity syndrome require counseling regarding gonadectomy and hormone replacement therapy and may require vaginal elongation for intercourse. Most women with Turner syndrome experience premature ovarian insufficiency and require long-term estrogen replacement. Women with Turner syndrome often have congenital anomalies and autoimmune disorders, which require regular monitoring and care during adulthood. The purpose of this review is to provide the obstetrician-gynecologist who cares for adult women with the most common disorders (differences) of sexual development conditions an outline of the current recommendations for screening and ongoing health care with particular emphasis on the underlying genetics, management of subfertility, infertility and sexual concerns, approach to hypogonadism, and understanding of associated comorbidities.

Mapping the effect of the X chromosome on the human brain: Neuroimaging evidence from Turner syndrome

In addition to determining sex, the X chromosome has long been considered to play a crucial role in brain development and intelligence. Turner syndrome (TS) is caused by the congenital absence of all or part of one of the X chromosomes in females. Thus, Turner syndrome provides a unique "knock-out model" for investigating how the X chromosome influences the human brain in vivo. Numerous cutting-edge neuroimaging techniques and analyses have been applied to investigate various brain phenotypes in women with TS, which have yielded valuable evidence toward elucidating the causal relationship between the X chromosome and human brain structure and function. In this review, we comprehensively summarize the recent progress made in TS-related neuroimaging studies and emphasize how these findings have enhanced our understanding of X chromosome function with respect to the human brain. Future investigations are encouraged to address the issues of previous TS neuroimaging studies and to further identify the biological mechanisms that underlie the function of specific X-linked genes in the human brain.

Clinical and genetic characteristics in a group of 45 patients with Turner syndrome (monocentric study)

Introduction

Recent years have seen a shift in perspective on Turner syndrome, as it is no longer considered a significant disability due to therapeutic advances. The delay of diagnosis and the underdiagnosis are common in Turner syndrome, especially because of the great phenotypic variability and lack of firm diagnostic criteria.

Aim

Our first aim was to assess the clinical and the cytogenetic characteristics and growth rate in growth hormone (GH)-treated patients as compared to those with spontaneous growth. The second aim was to analyze the Y chromosomal sequences.

Materials and methods

We analyzed 45 patients diagnosed with Turner syndrome in Genetic Pathology Centre of Cluj Emergency Children’s Hospital. We carried out a study of the clinical features, the correlations between the karyotype and the phenotype, and we also made a research of Y chromosome sequences.

Results

The average age at diagnosis was 8.9±5.4 years. A significant association was observed between the number of external phenotypical abnormalities and internal malformations (r=0.45), particularly the cardiovascular ones (r=0.44). Patients treated with GH showed improvement in growth rate, with final stature significantly better than in untreated patients; benefits following treatment were greater if diagnosis was made before the age of 5 years. Thirteen percent of patients experienced spontaneous and complete puberty, whereas 30% experienced incomplete puberty. Patients with the 45,X genotype had a greater stature deficit and a higher incidence of cardiac malformations, compared with patients with 45,X/46,XX mosaic karyotype. Y chromosome sequences were found in only one patient, who subsequently underwent gonadectomy.

Conclusion

The importance of this study resides, to the best of our knowledge, in the fact that the largest group of patients in Romania was analyzed and assessed. To draw firm conclusions on the most valuable clinical indicators for Turner syndrome diagnosis in clinical practice, studies on large groups of patients should be conducted.

Care of girls and women with Turner syndrome: beyond growth and hormones

Turner syndrome (TS), although considered a rare disease, is the most common sex chromosome abnormality in women, with an incident of 1 in 2500 female births. TS is characterized by distinctive physical features such as short stature, ovarian dysgenesis, an increased risk for heart and renal defects as well as a specific cognitive and psychosocial phenotype. Given the complexity of the condition, patients face manifold difficulties which increase over the lifespan. Furthermore, failures during the transitional phase to adult care result in moderate health outcomes and decreased quality of life. Guidelines on the optimal screening procedures and medical treatment are easy to find. However, recommendations for the treatment of the incriminating psychosocial aspects in TS are scarce. In this work, we first reviewed the literature on the cognitive and psychosocial development of girls with TS compared with normal development, from disclosure to young adulthood, and then introduce a psychosocial approach to counseling and treating patients with TS, including recommendations for age-appropriate psychological diagnostics. With this work, we aim to facilitate the integration of emphasized psychosocial care in state-of-the-art treatment for girls and women with TS.

Growth Hormone Treatment in Turner's Syndrome: A Real World Experience

OBJECTIVE

Short stature is a universal clinical feature of Turner's syndrome (TS). Growth failure begins in fetal life, and adults with TS are on an average 20 cm shorter than the normal female population. Since there is a paucity of data from India regarding the effect of growth hormone (GH) on TS patients, we retrospectively analyzed the data of TS patients who are on GH treatment.

METHODS

This hospital-based observational retrospective study was conducted in a tertiary care hospital of Hyderabad. The data such as height, weight, and bone age of 16 patients who are diagnosed with TS on GH therapy for at least 6 months were included in the study. All the patients were treated with human recombinant GH at the dose of 0.3 mg/kg/week administered as daily subcutaneous injections.

RESULTS

The mean age at diagnosis was 12.7 years. The mean height at the start of GH therapy was 1.26 m, and mean height standard deviation score (HSDS) was-0.61 when compared to Turner's specific reference data. With a mean duration of GH therapy of 25 months, the mean height at the end of therapy was 1.37 m and the mean height as per HSDS was + 0.37 resulting in a mean height gain of + 0.99 HSDS.

CONCLUSION

Our observation shows that girls with TS benefit from early diagnosis and initiation of treatment with GH.

Defects in the first wave of folliculogenesis in mouse XO ovaries

In mouse ovaries, the first wave of folliculogenesis perinatally starts near the medullary region, which directs the initial round of follicular growth soon after birth. At the same time, cortical primordial follicles start forming in the ovarian surface region, and then some are cyclically recruited for the second and subsequent rounds of follicular growth. Recent studies suggest different dynamics between the first and subsequent waves of follicular growth in postnatal ovaries. However, the phenotypic differences between these phases remain unclear. Here, we show direct evidence that XO female mice, a murine model for Turner Syndrome, lack the first wave of folliculogenesis. Our histopathological analyses of XX and XO littermates revealed a lack of anti-Müllerian hormone (AMH)-positive primary follicles in the XO ovaries by 4 days post partum (dpp). This loss of first follicles was also confirmed by histological bioassay for SRY-dependent SOX9 inducibility, a specific marker for the first follicular granulosa cells. In contrast, cortical primordial follicles formed properly in XO ovaries, and some of them formed primary and secondary follicles in the subcortical region by 7 dpp. They rapidly developed into late antral follicles, showing similarities to XX littermate ovaries by 21 dpp. These results suggest distinct X-monosomy effects between the first and subsequent waves of follicular growth, highlighting the high susceptibility to elimination of XO oocytes in the first wave of mammalian folliculogenesis.

Role of Genetics in the Etiology of Autistic Spectrum Disorder: Towards a Hierarchical Diagnostic Strategy

Progress in epidemiological, molecular and clinical genetics with the development of new techniques has improved knowledge on genetic syndromes associated with autism spectrum disorder (ASD). The objective of this article is to show the diversity of genetic disorders associated with ASD (based on an extensive review of single-gene disorders, copy number variants, and other chromosomal disorders), and consequently to propose a hierarchical diagnostic strategy with a stepwise evaluation, helping general practitioners/pediatricians and child psychiatrists to collaborate with geneticists and neuropediatricians, in order to search for genetic disorders associated with ASD. The first step is a clinical investigation involving: (i) a child psychiatric and psychological evaluation confirming autism diagnosis from different observational sources and assessing autism severity; (ii) a neuropediatric evaluation examining neurological symptoms and developmental milestones; and (iii) a genetic evaluation searching for dysmorphic features and malformations. The second step involves laboratory and if necessary neuroimaging and EEG studies oriented by clinical results based on clinical genetic and neuropediatric examinations. The identification of genetic disorders associated with ASD has practical implications for diagnostic strategies, early detection or prevention of co-morbidity, specific treatment and follow up, and genetic counseling.

Wish to conceive and concerns to develop cardiovascular complications during pregnancy in patients with Turner syndrome

INTRODUCTION

Turner syndrome (TS) is associated with subfertility and infertility. Nevertheless, an increasing number of women become pregnant through oocyte donation. The wish to conceive may be negatively influenced by the fear of cardiovascular complications. The aim was to investigate the wish to conceive and the concerns about cardiovascular complications during pregnancy in women with TS.

METHODS

The patient association for TS invited all members of ≥18 years old (n = 344) to complete a specifically developed, disease-specific questionnaire, including questions about fertility, wish to conceive, attempts and concerns. Results were compared with previously published results of this questionnaire in women with congenital heart disease.

RESULTS

The questionnaire was completed by 89 women (median age 30.1 years, Q1-Q3 = 22.9-39.4). Of them, 51% had 45, X0-monosomy and 38% had ≥1 cardiac abnormality. Seventeen women (19%) had attempted to become pregnant and 12 of them succeeded to become pregnant. Women who had not undertaken attempts to conceive (81%), considered themselves mainly too young or had no partner. Of the total sample, 58% were concerned about the influence of pregnancy on their cardiovascular status. This was higher (75%) in the sample of women with TS and cardiac abnormalities, than in women with congenital heart disease from a previously published cohort (21%), (p < .001). There were no differences in concerns about pregnancy complications between women with TS who respectively had or had not attempted to become pregnant.

DISCUSSION

Women with TS, especially those with cardiac abnormalities, show serious concerns about the risks pregnancy may have. Patients should be timely counseled and specifically asked about their concerns. Psychosocial care should be provided when necessary.

Gradually increasing ethinyl estradiol for Turner syndrome may produce good final height but not ideal BMD

Estrogen replacement therapy in Turner syndrome should theoretically mimic the physiology of healthy girls. The objective of this study was to describe final height and bone mineral density (BMD) in a group of 17 Turner syndrome patients (group E) who started their ethinyl estradiol therapy with an ultra-low dosage (1-5 ng/kg/day) from 9.8-13.7 years. The subjects in group E had been treated with GH 0.35 mg/kg/week since the average age of 7.4 years. The 30 subjects in group L, one of the historical groups, were given comparable doses of GH, and conjugated estrogen 0.3125 mg/week ∼0.3125 mg/day was initiated at 12.2-18.7 years. The subjects in group S, the other historical group, were 21 patients who experienced breast development and menarche spontaneously. Final height (height gain < 2 cm/year) in group E was 152.4 ± 3.4 cm and the standard deviation (SD) was 2.02 ± 0.62 for Turner syndrome. The final height in group L was 148.5 ± 3.0 cm with a SD of 1.30 ± 0.55, which was significantly different from the values for group E. The volumetric BMD of group S (0.290 ± 0.026 g/cm³) was significantly different from that of group L or E (0.262 or 0.262 g/cm³ as a mean, respectively). This is the first study of patients with Turner syndrome where estrogen was administered initially in an ultra-low dose and then increased gradually. Our estrogen therapy in group E produced good final height but not ideal BMD.

Continuous measurement of aortic dimensions in Turner syndrome: a cardiovascular magnetic resonance study

BACKGROUND

Severity of thoracic aortic disease in Turner syndrome (TS) patients is currently described through measures of aorta size and geometry at discrete locations. The objective of this study is to develop an improved measurement tool that quantifies changes in size and geometry over time, continuously along the length of the thoracic aorta.

METHODS

Cardiovascular magnetic resonance (CMR) scans for 15 TS patients [41 ± 9 years (mean age ± standard deviation (SD))] were acquired over a 10-year period and compared with ten healthy gender and age-matched controls. Three-dimensional aortic geometries were reconstructed, smoothed and clipped, which was followed by identification of centerlines and planes normal to the centerlines. Geometric variables, including maximum diameter and cross-sectional area, were evaluated continuously along the thoracic aorta. Distance maps were computed for TS and compared to the corresponding maps for controls, to highlight any asymmetry and dimensional differences between diseased and normal aortae. Furthermore, a registration scheme was proposed to estimate localized changes in aorta geometry between visits. The estimated maximum diameter from the continuous method was then compared with corresponding manual measurements at 7 discrete locations for each visit and for changes between visits.

RESULTS

Manual measures at the seven positions and the corresponding continuous measurements of maximum diameter for all visits considered, correlated highly (R-value = 0.77, P < 0.01). There was good agreement between manual and continuous measurement methods for visit-to-visit changes in maximum diameter. The continuous method was less sensitive to inter-user variability [0.2 ± 2.3 mm (mean difference in diameters ± SD)] and choice of smoothing software [0.3 ± 1.3 mm]. Aortic diameters were larger in TS than controls in the ascending [TS: 13.4 ± 2.1 mm (mean distance ± SD), Controls: 12.6 ± 1 mm] and descending [TS: 10.2 ± 1.3 mm (mean distance ± SD), Controls: 9.5 ± 0.9 mm] thoracic aorta as observed from the distance maps.

CONCLUSIONS

An automated methodology is presented that enables rapid and precise three-dimensional measurement of thoracic aortic geometry, which can serve as an improved tool to define disease severity and monitor disease progression.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier - NCT01678274 . Registered - 08.30.2012.

The Consequences of Chromosome Segregation Errors in Mitosis and Meiosis

Mistakes during cell division frequently generate changes in chromosome content, producing aneuploid or polyploid progeny cells. Polyploid cells may then undergo abnormal division to generate aneuploid cells. Chromosome segregation errors may also involve fragments of whole chromosomes. A major consequence of segregation defects is change in the relative dosage of products from genes located on the missegregated chromosomes. Abnormal expression of transcriptional regulators can also impact genes on the properly segregated chromosomes. The consequences of these perturbations in gene expression depend on the specific chromosomes affected and on the interplay of the aneuploid phenotype with the environment. Most often, these novel chromosome distributions are detrimental to the health and survival of the organism. However, in a changed environment, alterations in gene copy number may generate a more highly adapted phenotype. Chromosome segregation errors also have important implications in human health. They may promote drug resistance in pathogenic microorganisms. In cancer cells, they are a source for genetic and phenotypic variability that may select for populations with increased malignance and resistance to therapy. Lastly, chromosome segregation errors during gamete formation in meiosis are a primary cause of human birth defects and infertility. This review describes the consequences of mitotic and meiotic errors focusing on novel concepts and human health.

The ageing genome, clonal mosaicism and chronic disease

Clonal mosaicism arises when a postzygotic mutational event is detectable in subpopulations of cells as an alternative genotype while not present in the germline genome. Although described in a subset of pediatric disorders, new genomic technologies have detected higher than anticipated frequencies of clonal mosaicism in adult population studies, stimulating investigation as to how clonal mosaicism could contribute to chronic human diseases, such as cancer, diabetes and neurodegenerative disorders. It has also been postulated to be an important mechanism for functional cellular diversity, including the brain. Early studies have characterized the spectrum of detectable mosaic alterations and have begun to investigate whether detectable mosaicism could be important as an overall biomarker for risk or in the case of hematologic cancers, identification of preleukemic clones.

The Effects of the X Chromosome on Intrinsic Functional Connectivity in the Human Brain: Evidence from Turner Syndrome Patients

Turner syndrome (TS), a disorder caused by the congenital absence of one of the 2 X chromosomes in female humans, provides a valuable human "knockout model" for studying the functions of the X chromosome. At present, it remains unknown whether and how the loss of the X chromosome influences intrinsic functional connectivity (FC), a fundamental phenotype of the human brain. To address this, we performed resting-state functional magnetic resonance imaging and specific cognitive assessments on 22 TS patients and 17 age-matched control girls. A novel data-driven approach was applied to identify the disrupted patterns of intrinsic FC in TS. The TS girls exhibited significantly reduced whole-brain FC strength within the bilateral postcentral gyrus/intraparietal sulcus, angular gyrus, and cuneus and the right cerebellum. Furthermore, a specific functional subnetwork was identified in which the intrinsic FC between nodes was mostly reduced in TS patients. Particularly, this subnetwork is composed of 3 functional modules, and the disruption of intrinsic FC within one of these modules was associated with the deficits of TS patients in math-related cognition. Taken together, these findings provide novel insight into how the X chromosome affects the human brain and cognition, and emphasize an important role of X-linked genes in intrinsic neural coupling.

Meiotic Divisions: No Place for Gender Equality

In multicellular organisms the fusion of two gametes with a haploid set of chromosomes leads to the formation of the zygote, the first cell of the embryo. Accurate execution of the meiotic cell division to generate a female and a male gamete is required for the generation of healthy offspring harboring the correct number of chromosomes. Unfortunately, meiosis is error prone. This has severe consequences for fertility and under certain circumstances, health of the offspring. In humans, female meiosis is extremely error prone. In this chapter we will compare male and female meiosis in humans to illustrate why and at which frequency errors occur, and describe how this affects pregnancy outcome and health of the individual. We will first introduce key notions of cell division in meiosis and how they differ from mitosis, followed by a detailed description of the events that are prone to errors during the meiotic divisions.

Impaired Vascular Function of the Aorta in Adolescents with Turner Syndrome

To investigate intrinsic vascular abnormalities of the ascending aorta before adulthood in Turner syndrome patients (TS), we compared 25 adolescent TS patients (mean age 14.6 ± 3.4 years) and 16 healthy controls from a university hospital. Blood pressure and other vascular indices were evaluated using echocardiography such as aortic strain, stiffness index, distensibility, and pulse wave velocity. Aortic strain (0.1237 vs. 0.1865, respectively; P = 0.003) and aortic distensibility (0.0049 vs. 0.0081, P = 0.002) were significantly lower in the TS group than in the controls. The fractional area change on velocity vector imaging was also lower in TS patients (29.05 vs. 36.19, P = 0.002). These findings were still observed after adjustment for age, body mass index, and systolic blood pressure. The aortic stiffness index was greater in the TS patients than in the control group (6.79 vs. 3.34, P = 0.02). The pulse wave velocity and ascending aorta diameter did not significantly differ between the TS and control groups. Blood pressures were significantly higher in the TS patients than in the controls (systolic, 120.4 vs. 108.4 mmHg, P = 0.001; diastolic 71.5 vs. 61.7 mmHg, P < 0.001). Although the dimensional changes in the aorta were not clearly observed in adolescents with TS, the elastic properties of the aorta were significantly decreased in TS patients as compared to control subjects.

Concomitant occurrence of Turner syndrome and growth hormone deficiency

Turner syndrome (TS) is a genetic disorder in phenotypic females that has characteristic physical features and presents as partial or complete absence of the second sex chromosome. Growth hormone deficiency (GHD) is a condition caused by insufficient release of growth hormone from the pituitary gland. The concomitant occurrence of TS and GHD is rare and has not yet been reported in Korea. Here we report 2 cases of TS and GHD. In case 1, GHD was initially diagnosed. Karyotyping was performed because of the presence of the typical phenotype and poor response to growth hormone therapy, which revealed 45,X/45,X+mar. The patient showed increased growth velocity after the growth hormone dose was increased. In case 2, a growth hormone provocation test and chromosomal analysis were performed simultaneously because of decreased growth velocity and the typical TS phenotype, which showed GHD and a mosaic karyotype of 45,X/46,XX. The patient showed spontaneous pubertal development. In female patients with short stature, it is important to perform a throughout physical examination and test for hormonal and chromosomal abnormalities because diagnostic accuracy is important for treatment and prognosis.

Severe hemophilia in a girl infant with mosaic Turner syndrome and persistent hyperplastic primary vitreous

A 6-month-old girl was referred by an ophthalmologist because of postoperative bleeding. She was scheduled for operation because of persistent hyperplastic primary vitreous. Workups were done and prolonged partial thromboplastin time with normal platelet count, normal bleeding time, and prothrombin time were detected. There was negative family history of bleeding tendency in both maternal and paternal family, so at the first step, Factor XI assay was requested which was normal. Then, von Willebrand factor and factor VIII were assayed which was 127% and less than 1%, respectively. Severe factor VIII deficiency was not suspected in a girl unless in siblings of a hemophilic patient who gets married with her carrier cousin. Chromosomal study and genetic testing were requested and mosaic Turner syndrome (45 XO) with ring X (p22, 2q13) along with inversion 22 (hemizygote) was detected. Abdominal and pelvic sonography showed absence of both ovaries with presence of infantile uterus. Maternal genetic study was in favor of carrier of hemophilia (heterozygote inversion 22). To the best of our knowledge, this is the first case of association of Turner syndrome with severe hemophilia A and persistent hyperplastic primary vitreous.

Genetics of primary ovarian insufficiency

Primary ovarian insufficiency (POI) is characterized by a loss of ovarian function before the age of 40 and account for one major cause of female infertility. POI relevance is continuously growing because of the increasing number of women desiring conception beyond 30 years of age, when POI prevalence is >1%. POI is highly heterogeneous and can present with ovarian dysgenesis and primary amenorrhea, or with secondary amenorrhea, and it can be associated with other congenital or acquired abnormalities. In most cases POI remains classified as idiopathic. However, the age of menopause is an inheritable trait and POI has a strong genetic component. This is confirmed by the existence of several candidate genes, experimental and natural models. The variable expressivity of POI defect may indicate that, this disease may frequently be considered as a multifactorial or oligogenic defect. The most common genetic contributors to POI are the X chromosome-linked defects. Here, we review the principal X-linked and autosomal genes involved in syndromic and non-syndromic forms of POI with the expectation that this list will soon be upgraded, thus allowing the possibility to predict the risk of an early age at menopause in families with POI.

A case of 46,XX dysgenesis and marked tall stature; the need for caution in interpreting array comparative genomic hybridization (CGH)

BACKGROUND

Gonadal dysgenesis with an apparently normal 46,XX karyotype is a rare cause of hypergonadotrophic hypogonadism. Tall stature is not a widely recognized association.

CASE REPORT

A 15-year-old girl presented with primary amenorrhoea. Examination showed a non-dysmorphic girl of normal intellect with no breast development (Tanner stage B1P4A1) who was tall compared with her parents: height standard deviation score (SDS) +1.56 vs. midparental height of +0.23 SDS, and slim build (weight -0.13 SDS). Investigations showed a 46,XX karyotype, elevated gonadotropins (FSH 119 and LH 33.7 IU/L), serum estradiol <5 pmol/L, uterine length 3.75 cm with cylindrical shape, and absent ovaries on ultrasound. Initially, a 364055-bp deletion on Xp21.2 was reported on array CGH. However, repeat analysis using BlueGnome CytoChip ISCA 4x180k v2.0 array was normal. With oral ethinyl estradiol induction puberty progressed to B4P4A2 but aged 18.4 years, the patient was remarkably tall with height SDS +2.88, weight SDS +0.97.

CONCLUSIONS

Caution is needed in interpreting small changes with array CGH, particularly with the older assays. We postulate that the genetic change causing 46,XX gonadal dysgenesis in our patient may have also resulted in unsuppressed somatic growth. More critical height assessment, including parental height measurement, of future patients with 46,XX gonadal dysgenesis is recommended in order to determine whether or not a true association with tall stature may be present in certain cases.

XCI-escaping gene KDM5C contributes to ovarian development via downregulating miR-320a

Mechanisms underlying female gonadal dysgenesis remain unclarified and relatively unstudied. Whether X-chromosome inactivation (XCI)-escaping genes and microRNAs (miRNAs) contribute to this condition is currently unknown. We compared 45,X Turner Syndrome women with 46,XX normal women, and investigated differentially expressed miRNAs in Turner Syndrome through plasma miRNA sequencing. We found that miR-320a was consistently upregulated not only in 45,X plasma and peripheral blood mononuclear cells (PBMCs), but also in 45,X fetal gonadal tissues. The levels of miR-320a in PBMCs from 45,X, 46,XX, 46,XY, and 47,XXY human subjects were inversely related to the expression levels of XCI-escaping gene KDM5C in PBMCs. In vitro models indicated that KDM5C suppressed miR-320a transcription by directly binding to the promoter of miR-320a to prevent histone methylation. In addition, we demonstrated that KITLG, an essential gene for ovarian development and primordial germ cell survival, was a direct target of miR-320a and that it was downregulated in 45,X fetal gonadal tissues. In conclusion, we demonstrated that downregulation of miR-320a by the XCI-escaping gene KDM5C contributed to ovarian development by targeting KITLG.

Genetics of inherited cardiocutaneous syndromes: a review

The life of a human being originates as a single cell which, under the influence of certain factors, divides sequentially into multiple cells that subsequently become committed to develop and differentiate into the different structures and organs. Alterations occurring early on in the development process may lead to fetal demise in utero. Conversely, abnormalities at later stages may result in structural and/or functional abnormalities of varying severities. The cardiovascular system and skin share certain developmental and structural factors; therefore, it is not surprising to find several inherited syndromes with both cardiac and skin manifestations. Here, we will review the overlapping pathways in the development of the skin and heart, as well as the resulting syndromes. We will also highlight several cutaneous clues that may help physicians screen and uncover cardiac anomalies that may be otherwise hidden and result in sudden cardiac death.

Increasing School Nurse Awareness of Turner Syndrome

Turner syndrome, a genetic disorder that affects only females, can cause various physical, emotional, and educational disabilities. This disorder may go undiagnosed until school age or later. Short stature and lack of spontaneous puberty are common characteristics and can lead to teasing by peers. Some experience attention deficit and the inability to notice social cues that can be misinterpreted as behavioral issues. Others have visual-spatial deficits that can lead to math learning disabilities and difficulty driving. Because the child with Turner syndrome often has a higher verbal than nonverbal intelligence, learning disabilities may be difficult to identify and often are overlooked. The school nurse, through mandated screenings and routine student office visits, may be the first to recognize Turner syndrome. School nurses need to be aware of this disorder and related educational disabilities to provide early intervention to maximize student health and educational success.

Genetics of Congenital Heart Disease: Past and Present

Congenital heart disease is the most common congenital anomaly, representing an important cause of infant morbidity and mortality. Congenital heart disease represents a group of heart anomalies that include septal defects, valve defects, and outflow tract anomalies. The exact genetic, epigenetic, or environmental basis of congenital heart disease remains poorly understood, although the exact mechanism is likely multifactorial. However, the development of new technologies including copy number variants, single-nucleotide polymorphism, next-generation sequencing are accelerating the detection of genetic causes of heart anomalies. Recent studies suggest a role of small non-coding RNAs, micro RNA, in congenital heart disease. The recently described epigenetic factors have also been found to contribute to cardiac morphogenesis. In this review, we present past and recent genetic discoveries in congenital heart disease.

Next generation sequencing identifies abnormal Y chromosome and candidate causal variants in premature ovarian failure patients

Premature ovarian failure (POF) is characterized by heterogeneous genetic causes such as chromosomal abnormalities and variants in causal genes. Recently, development of techniques made next generation sequencing (NGS) possible to detect genome wide variants including chromosomal abnormalities. Among 37 Korean POF patients, XY karyotype with distal part deletions of Y chromosome, Yp11.32-31 and Yp12 end part, was observed in two patients through NGS. Six deleterious variants in POF genes were also detected which might explain the pathogenesis of POF with abnormalities in the sex chromosomes. Additionally, the two POF patients had no mutation in SRY but three non-synonymous variants were detected in genes regarding sex reversal. These findings suggest candidate causes of POF and sex reversal and show the propriety of NGS to approach the heterogeneous pathogenesis of POF.

Incidence of X and Y Chromosomal Aneuploidy in a Large Child Bearing Population

BACKGROUND

X&Y chromosomal aneuploidies are among the most common human whole-chromosomal copy number changes, but the population-based incidence and prevalence in the child-bearing population is unclear.

METHODS

This retrospective analysis of prospectively collected data leveraged a routine non-invasive prenatal test (NIPT) using parental genotyping to estimate the population-based incidence of X&Y chromosome variations in this population referred for NIPT (generally due to advanced maternal age).

RESULTS

From 141,916 women and 29,336 men, 119 X&Y chromosomal abnormalities (prevalence: 1 in 1,439) were identified. Maternal findings include: 43 cases of 45,X (40 mosaic); 30 cases of 47,XXX (12 mosaic); 3 cases of 46,XX uniparental disomy; 2 cases of 46,XY/46,XX; 23 cases of mosaicism of unknown type; 2 cases of 47,XX,i(X)(q10). Paternal findings include: 2 cases of 47,XXY (1 mosaic); 10 cases of 47,XYY (1 mosaic); 4 partial Y deletions.

CONCLUSIONS

Single chromosome aneuploidy was present in one of every 1,439 individuals considered in this study, showing 47,XXX; 47,XX,i(X)(q10); 47,XYY; 47,XXY, partial Y deletions, and a high level of mosaicism for 45,X. This expands significantly our understanding of X&Y chromosomal variations and fertility issues, and is critical for families and adults affected by these disorders. This current and extensive information on fertility will be beneficial for genetic counseling on prenatal diagnoses as well as for newly diagnosed postnatal cases.

A Track Record on SHOX: From Basic Research to Complex Models and Therapy

SHOX deficiency is the most frequent genetic growth disorder associated with isolated and syndromic forms of short stature. Caused by mutations in the homeobox gene SHOX, its varied clinical manifestations include isolated short stature, Léri-Weill dyschondrosteosis, and Langer mesomelic dysplasia. In addition, SHOX deficiency contributes to the skeletal features in Turner syndrome. Causative SHOX mutations have allowed downstream pathology to be linked to defined molecular lesions. Expression levels of SHOX are tightly regulated, and almost half of the pathogenic mutations have affected enhancers. Clinical severity of SHOX deficiency varies between genders and ranges from normal stature to profound mesomelic skeletal dysplasia. Treatment options for children with SHOX deficiency are available. Two decades of research support the concept of SHOX as a transcription factor that integrates diverse aspects of bone development, growth plate biology, and apoptosis. Due to its absence in mouse, the animal models of choice have become chicken and zebrafish. These models, therefore, together with micromass cultures and primary cell lines, have been used to address SHOX function. Pathway and network analyses have identified interactors, target genes, and regulators. Here, we summarize recent data and give insight into the critical molecular and cellular functions of SHOX in the etiopathogenesis of short stature and limb development.

The impact of FMR1 gene mutations on human reproduction and development: a systematic review

PURPOSE

This is a comprehensive review of the literature in this field attempting to put the FMR1 gene and its evaluation into context, both in general and for the reproductive health audience.

METHODS

Online database search of publications with systematic review of all papers relevant to ovarian reserve and assisted reproduction was done.

RESULTS

Relevant papers were identified and assessed, and an attempt was made to understand, rationalize and explain the divergent views in this field of study. Seminal and original illustrations were employed.

CONCLUSIONS

FMR1 is a highly conserved gene whose interpretation and effect on outcomes remains controversial in the reproductive health setting. Recent re-evaluations of the commonly accepted normal range have yielded interesting tools for possibly explaining unexpected outcomes in assisted reproduction. Fragile X investigations should perhaps become more routinely assessed in the reproductive health setting, particularly following a failed treatment cycle where oocyte quality is thought to be a contributing factor, or in the presence of a surprise finding of diminished ovarian reserve in a young patient.

Physiological Aspects of Female Fertility: Role of the Environment, Modern Lifestyle, and Genetics

Across the Western World there is an increasing trend to postpone childbearing. Consequently, the negative influence of age on oocyte quality may lead to a difficulty in conceiving for many couples. Furthermore, lifestyle factors may exacerbate a couple's difficulty in conceiving due mainly to the metabolic influence of obesity; however, the negative impacts of low peripheral body fat, excessive exercise, the increasing prevalence of sexually transmitted diseases, and smoking all have significant negative effects on fertility. Other factors that impede conception are the perceived increasing prevalence of the polycystic ovary syndrome, which is further exacerbated by obesity, and the presence of uterine fibroids and endometriosis (a progressive pelvic inflammatory disorder) which are more prevalent in older women. A tendency for an earlier sexual debut and to have more sexual partners has led to an increase in sexually transmitted diseases. In addition, there are several genetic influences that may limit the number of oocytes within the ovary; consequently, by postponing attempts at childbearing, a limitation of oocyte number may become evident, whereas in previous generations with earlier conception this potentially reduced reproductive life span did not manifest in infertility. Environmental influences on reproduction are under increasing scrutiny. Although firm evidence is lacking however, dioxin exposure may be linked to endometriosis, phthalate exposure may influence ovarian reserve, and bisphenol A may interfere with oocyte development and maturation. However, chemotherapy or radiotherapy is recognized to lead to ovarian damage and predispose the woman to ovarian failure.

Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome

To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2 Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events. X mosaicism frequency increases with age (0.11% in 50-year olds; 0.45% in 75-year olds), as reported for Y and autosomes. Methylation array analyses of 33 women with X mosaicism indicate events preferentially involve the inactive X chromosome. Our results provide further evidence that the sex chromosomes undergo mosaic events more frequently than autosomes, which could have implications for understanding the underlying mechanisms of mosaic events and their possible contribution to risk for chronic diseases.

Veia cava superior esquerda persistente: relato de caso

O pleno conhecimento da anatomia vascular torácica é de suma importância para os profissionais envolvidos na realização de procedimentos invasivos como a punção de acesso venoso central. A persistência da veia cava superior esquerda é a malformação venosa torácica mais frequente, e seu diagnóstico costuma ser incidental. Apresentamos o caso de uma paciente de 14 anos em que o diagnóstico de veia cava superior esquerda persistente foi incidental em exame de imagem de controle após colocação de cateter venoso totalmente implantável. A paciente não apresentou dificuldade de infusão de quimioterapia pelo cateter e não houve complicações relacionadas ao cateter.

Identification of Y-Chromosome Sequences in Turner Syndrome

OBJECTIVES

To investigate the presence of Y-chromosome sequences and determine their frequency in patients with Turner syndrome.

METHODS

The study included 23 patients with Turner syndrome from Brazil, who gave written informed consent for participating in the study. Cytogenetic analyses were performed in peripheral blood lymphocytes, with 100 metaphases per patient. Genomic DNA was also extracted from peripheral blood lymphocytes, and gene sequences DYZ1, DYZ3, ZFY and SRY were amplified by Polymerase Chain Reaction.

RESULTS

The cytogenetic analysis showed a 45,X karyotype in 9 patients (39.2 %) and a mosaic pattern in 14 (60.8 %). In 8.7 % (2 out of 23) of the patients, Y-chromosome sequences were found. This prevalence is very similar to those reported previously. The initial karyotype analysis of these patients did not reveal Y-chromosome material, but they were found positive for Y-specific sequences in the lymphocyte DNA analysis.

CONCLUSION

The PCR technique showed that 2 (8.7 %) of the patients with Turner syndrome had Y-chromosome sequences, both presenting marker chromosomes on cytogenetic analysis.

Familial Turner syndrome: the importance of information

Turner syndrome is a common genetic disorder with an incidence of 1 in 2500 live births. Spontaneous fertility is rare in such patients and is most likely in women with mosaicism or very distal Xp deletions. The authors report an unusual case of familial Turner syndrome in a woman with mosaicism 45,X/46,Xdel(Xp) karyotype with three documented spontaneous pregnancies, which resulted in two daughters with 46,Xdel(X)(p11.4)mat karyotype and a healthy son. The mother was first diagnosed by the age of 11 and did not receive contraceptive medication, due to information that she would be infertile. Both daughters were referred to an endocrinology unit and are now under growth hormone treatment, and have been growing in the 3rd percentile. This family illustrates the complexity and difficulties in counseling, follow-up and treatment in Turner syndrome, namely referring to a tertiary center, fertility and treatment such as growth hormone and hormonal replacement, due to the heterogeneity of the clinical spectrum.

Arterial hypertension in Turner syndrome: a review of the literature and a practical approach for diagnosis and treatment

Turner syndrome is a rare chromosomal disorder with complete or partial absence of one X chromosome that only occurs in women. Clinical presentation is variable, but congenital and acquired cardiovascular diseases are frequently associated diseases that add significantly to the increased morbidity and mortality in Turner syndrome patients. Arterial hypertension is reported in 13-58% of adult Turner syndrome patients and confers an increased risk for stroke and aortic dissection. Hypertension can be present from childhood on and is reported in one-quarter of the paediatric Turner syndrome patients. This article reviews the prevalence and cause of arterial hypertension in Turner syndrome and describes the relationship between blood pressure, aortic dilation and increased cardiovascular risk. We compare current treatment strategies and also propose an integrated practical approach for the diagnosis and treatment of hypertension in Turner syndrome applicable in daily practice.

Sonographic Detection of an Unknown Chromosomal Disorder in Utero

Obstetric sonography has a long-standing reputation assisting in the detection of chromosomal abnormalities in utero. Additional diagnostic testing can be performed to confirm a genetic anomaly, including noninvasive prenatal testing, nuchal translucency, and amniocentesis. Comprehensively studied chromosomal abnormalities include trisomies 21, 13, and 18 and monosomy X. Although chromosomal abnormalities cannot be treated, they can be managed and monitored by serial sonograms and genetic counseling prior to delivery, allowing for preparation for a special needs child. This case study presents a fetus with multiple anomalies, including a rare presentation of cystic hygroma. In this specific case, the patient refused a genetic amniocentesis, leaving the cause(s) of the multiple anomalies unknown.

X-chromosome gene dosage as a determinant of impaired pre and postnatal growth and adult height in Turner syndrome

OBJECTIVE

Short stature is a key aspect of the phenotype of patients with Turner syndrome (TS). SHOX haploinsufficiency is responsible for about two-thirds of the height deficit. The aim was to investigate the effect of X-chromosome gene dosage on anthropometric parameters at birth, spontaneous height, and adult height (AH) after growth hormone (GH) treatment.

DESIGN

We conducted a national observational multicenter study.

METHODS

Birth parameter SDS for gestational age, height, and AH before and after GH treatment respectively, and height deficit with respect to target height (SDS) were classified by karyotype subgroup in a cohort of 1501 patients with TS: 45,X (36%), isoXq (19%), 45,X/46,XX (15%), XrX (7%), presence of Y (6%), or other karyotypes (17%).

RESULTS

Birth weight, length (P<0.0001), and head circumference (P<0.001), height and height deficit with respect to target height (SDS) before GH treatment, at a median age of 8.8 (5.3-11.8) years and after adjustment for age and correction for multiple testing (P<0.0001), and AH deficit with respect to target height at a median age of 19.3 (18.0-21.8) years and with additional adjustment for dose and duration of GH treatment (P=0.006), were significantly associated with karyotype subgroup. Growth retardation tended to be more severe in patients with XrX, isoXq, and, to a lesser extent, 45,X karyotypes than in patients with 45,X/46,XX karyotypes or a Y chromosome.

CONCLUSION

These data suggest that haploinsufficiency for an unknown Xp gene increases the risk of fetal and postnatal growth deficit and short AH with respect to target height after GH therapy.