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Expanding the Clinical Phenotype of Sexual Chromosome Aneuploidies: Description of Cases Detected by Newborn Screening
Abstract
Aim: Sex chromosome aneuploidies (SCA) are the most common chromosome aberrations in humans, their clinical recognition at birth is challenging and so underdiagnosed. We describe the clinical features of patients detected by newborn screening for SCA, to provide new findings that help clinicians suspect these disorders. Subjects and Methods: This is a transverse descriptive study of infants identified through a newborn screening pilot study for SCA in two Mexican public hospitals in Monterrey, N.L., and referred to Genetics Department for karyotyping. Seventeen patients with a diagnosed SCA were examined by a clinical geneticist. Results: Triple X Syndrome patients (3) had epicanthus and low nasal root in 100%, pre-auricular pits or tags, dysmorphic earlobes and hyper-pigmented macules in 66%. Four out of the five patients with Turner Syndrome presented mosaicism and the most frequent features were pigmented skin defects (80%), telecanthus and/or epicanthus (60%) congenital heart defects, hands or feet edema, posterior low hairline and high palate (40%). Klinefelter Syndrome patients (5), showed telecanthus or epicanthus (60%); and in 40% bilateral fifth finger clinodactyly or hypospadias was found. All patients with XYY Syndrome (4) had hypertelorism and 75% micropenis. Conclusions: Patients with SCA showed traits that most of the time are unnoticed or identified as normal variants. In this study we found that minor traits, such as the micropenis, which had not previously been reported as part of the XYY syndrome could underlie a sex chromosome anomaly, this grants particular importance to a detailed examination of newborns by health personnel.
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Aims:
In this study, we examined the doses of the stature homeobox (SHOX), vesicle-associated membrane protein 7 (VAMP7), and SRY genes to establish a protocol for using peripheral blood samples deposited on filter paper for the screening of sex chromosome aneuploidy in neonates. We also measured correlations with karyotypes to assess this method as a neonatal screening strategy.
Materials and methods:
This was an observational, descriptive, comparative blind study. Thirty-two healthy young adults (17 women, 15 men; age, ≥18 years), four patients with known sex chromosome aneuploidy (positive control group), and 1000 healthy newborns were included. Gene dosages were determined using quantitative real-time polymerase chain reaction (RT-PCR). Values with standard deviations (SDs) of three or more were considered abnormal.
Results:
Men and women differed in the gene dosage of the SRY gene. Cases with Turner syndrome showed values below 3 SDs for SHOX and VAMP7 genes, and cases with Klinefelter syndrome showed values above 3 SDs for SHOX and VAMP7 genes. Two suspected cases of sex chromosome aneuploidy were diagnosed using our neonatal screening strategy; these cases were confirmed as Turner syndrome and 47,XYY syndrome by karyotyping.
Conclusions:
Our data establish a basis for the determination of chromosomal sex and neonatal screening of sex chromosome aneuploidy using RT-PCR.
We describe the case of a ten-year-old girl with short stature and 45,X/47,XXX genotype. She also suffered from vesicoureteric reflux and kidney dysfunction prior to having surgery on her ureters. Otherwise, she does not have any of the characteristics of Turner nor Triple X syndrome. It has been shown that this mosaic condition as well as other varieties creates a milder phenotype than typical Turner syndrome, which is what we mostly see in our patient. However, this patient is a special case, because she is exceptionally short. Overall, one cannot predict the resultant phenotype in these mosaic conditions. This creates difficulty in counseling parents whose children or fetuses have these karyotypes.
Turner Syndrome is an unfavorable genetic condition with a prevalence of 1:2500 in newborn girls. Prompt and effective diagnosis is very important to appropriately monitor the co-morbidities. The aim of the present study was to propose a feasible and practical molecular diagnostic tool for newborn screening by quantifying the gene dosage of the SHOX, VAMP7, XIST, UBA1 and SRY 32 genes by qPCR in individuals with a diagnosis of complete X monosomy, as well as those with Turner Syndrome variants, and then compare the results to controls without chromosomal abnormalities. According to our results, the most useful markers for these chromosomal variants were the genes found in the pseudoautosomic regions 1 and 2 (PAR1 and PAR2) because differences in gene dosage (RQ) between groups were more evident in SHOX and VAMP7 gene expression. Therefore, we conclude that these markers are useful for early detection in aneuploidies involving sex chromosomes.
A 46-year-old female presented to the emergency room due to the chief complaint of left-sided weakness. By imaging study, she was diagnosed with cerebral infarction. Thrombolytic and antiplatelet agents were not considered due to the "golden hour" for treatment having passed and a low platelet count. The peripheral blood smear, bone marrow biopsy, and aspirate findings were consistent with immune thrombocytopenic purpura. The chromosome analysis revealed the 47,XXX karyotype. To the best of our knowledge, this is the first case report associated with the comorbidities of cerebral infarction, idiopathic thrombocytopenic purpura, and triple X syndrome.
Background:
Turner syndrome (TS) is a common genetic disorder caused by abnormalities of the X chromosome. We aimed to describe the phenotypic characteristics of TS patients and evaluate their association with presenting clinical characteristics and time at diagnosis.
Methods:
We studied females diagnosed with TS at King Abdul Aziz Medical City (KAMC), Riyadh between 1983 and 2010. Patients were classified based upon karyotype into females with classical monosomy 45,X (group A) and females with other X chromosome abnormalities (mosaic 45,X/46,XX, Xqisochromosomes, Xp or Xq deletion) (group B). Clinical features of the two groups were analyzed.
Results:
Of the 52 patients included in the study, 16(30.8%) were diagnosed with classical monosomy 45,X and the rest with other X chromosome abnormalities. Only 19(36.5%) patients were diagnosed in infancy and the remaining during childhood or later (odds ratio (OR) = 4.5,95%CI 1.27-15.90, p=0.02). Short stature was universal in group A versus 77.8% in group B. All patients in group A had primary amenorrhea compared with 63.2% of those in group B (P = 0.04); the rest of group B had secondary amenorrhea. Cardiovascular abnormalities were higher in group A (OR=3.50, 95%CI 0.99-12.29, p-value =0.05). Renal defects and recurrent otitis media were similar in both groups.
Conclusion:
This study suggests that karyotype variations might affect the phenotype of TS; however, it may not reliably predict the clinical presentation. Chromosomal analysis for all suspected cases of TS should be promptly done at childhood in order to design an appropriate management plan early in life.
Reports on cases of epilepsy in Turner syndrome are rare and most of them have cortical developmental malformations. We report the case of a Taiwanese patient with mosaic Turner syndrome with generalized tonic-clonic epilepsy and asymmetrical lateral ventricles but no apparent cortical anomaly.
A 49-year-old Taiwanese woman without family history presented with infrequent generalized tonic-clonic epilepsy since she was 11 years old. On examination, her short stature, webbed neck, swelling of hands and feet, retrognathic face, and mild intellectual disability were noted. She had spontaneous menarche and regular menses. Brain magnetic resonance imaging showed asymmetrical lateral ventricles and diffuse subcortical white matter T2-weighted hyperintensities. Chromosome studies disclosed low aneuploid (10%) 45,X/46,XX/47,XXX mosaic Turner syndrome.
There is increasing evidence that epilepsy can be an uncommon presentation of Turner syndrome. Mosaic Turner syndrome with 47, XXX probably increases the risk of epilepsy but more research is needed to reach a conclusion. This case also strengthens our knowledge that Turner syndrome can be one of the pathologic bases of asymmetrical lateral ventricles. When a patient has idiopathic/cryptogenic epilepsy or asymmetrical lateral ventricles on brain images, the presence of a mild Turner phenotype warrants further chromosome studies.
Triple X syndrome is a sex chromosomal aneuploidy condition characterized by tall stature, microcephaly, hypertelorism, congenital abnormalities, and motor and language delays. It is mainly derived from maternal nondisjunctional errors during meiosis. To highlight the clinical features and diagnosis of triple X syndrome, we present a rare phenotype of the syndrome.
A 5.9 year-old girl was admitted to our hospital because of short stature. Both her height and weight were below the 3(rd) percentile compared to the normal peers. She was found with mild motor and speech delay. Laboratory investigation showed low level of IGF-1 and zinc, elevated estradiol level and normal result of arginine provocation test.
Our data suggest that triple X syndrome should also be suspected in patients with short stature, elevated estradiol and low level of IGF-1, even with normal result of arginine provocation test.
Triple X syndrome (47,XXX or trisomy X) is a relatively frequent cytogenetic condition with a large variety of physical and behavioural phenotypes.
Two adult patients with a triple X karyotype are described.
Their karyotype was unknown until some years ago. What these patients have in common is that they were diagnosed with a broader autism phenotype, they were sexually abused, they suffer from psychotic illness and they show challenging behaviour, suicidality and a decline in occupational capacity.
These gene-environment interactions are discussed. Gene-environment interactions may explain the variety of behavioural and psychiatric phenotypes in triple X syndrome. Ongoing atypical development in adults is hypothesized.
Gene-environment interactions and ongoing atypical development in adults should be taken into account in research concerning the psychiatric phenotype of developmental disorders, especially those involving triple X syndrome.
The objective of this study was to describe the prevalence of Klinefelter syndrome (KS) prenatally and postnatally in Denmark and determine the influence of maternal age. All chromosomal examinations in Denmark are registered in the Danish Cytogenetic Central Registry. Individuals with KS diagnosed prenatally or postnatally were extracted from the registry with information about age at the time of diagnosis and mother's age. In the period 1970-2000, 76,526 prenatal examinations on male fetuses resulted in the diagnosis of 163 fetuses with KS karyotype, corresponding to a prevalence of 213 per 100,000 male fetuses. Standardization according to maternal age resulted in a prevalence of 153 per 100,000 males. Postnatally, 696 males of 2,480,858 live born were diagnosed with KS, corresponding to a prevalence among adult men of approximately 40 per 100,000. Less than 10% of the expected number was diagnosed before puberty. Advanced maternal age had a significant impact on the prevalence. KS is severely under
Trisomy X is a sex chromosome anomaly with a variable phenotype caused by the presence of an extra X chromosome in females (47,XXX instead of 46,XX). It is the most common female chromosomal abnormality, occurring in approximately 1 in 1,000 female births. As some individuals are only mildly affected or asymptomatic, it is estimated that only 10% of individuals with trisomy X are actually diagnosed. The most common physical features include tall stature, epicanthal folds, hypotonia and clinodactyly. Seizures, renal and genitourinary abnormalities, and premature ovarian failure (POF) can also be associated findings. Children with trisomy X have higher rates of motor and speech delays, with an increased risk of cognitive deficits and learning disabilities in the school-age years. Psychological features including attention deficits, mood disorders (anxiety and depression), and other psychological disorders are also more common than in the general population. Trisomy X most commonly occurs as a result of nondisjunction during meiosis, although postzygotic nondisjunction occurs in approximately 20% of cases. The risk of trisomy X increases with advanced maternal age. The phenotype in trisomy X is hypothesized to result from overexpression of genes that escape X-inactivation, but genotype-phenotype relationships remain to be defined. Diagnosis during the prenatal period by amniocentesis or chorionic villi sampling is common. Indications for postnatal diagnoses most commonly include developmental delays or hypotonia, learning disabilities, emotional or behavioral difficulties, or POF. Differential diagnosis prior to definitive karyotype results includes fragile X, tetrasomy X, pentasomy X, and Turner syndrome mosaicism. Genetic counseling is recommended. Patients diagnosed in the prenatal period should be followed closely for developmental delays so that early intervention therapies can be implemented as needed. School-age children and adolescents benefit from a psychological evaluation with an emphasis on identifying and developing an intervention plan for problems in cognitive/academic skills, language, and/or social-emotional development. Adolescents and adult women presenting with late menarche, menstrual irregularities, or fertility problems should be evaluated for POF. Patients should be referred to support organizations to receive individual and family support. The prognosis is variable, depending on the severity of the manifestations and on the quality and timing of treatment.
The goal of this study was to contrast the cognitive phenotypes in boys with 47,XYY (XYY) karyotype and boys with 47,XXY karyotype [Klinefelter syndrome, (KS)], who share an extra copy of the X-Y pseudoautosomal region but differ in their dosage of strictly sex-linked genes.
Neuropsychological evaluation of general cognitive ability, language, memory, attention, visual-spatial abilities, visual-motor skills, and motor function.
Study cohort: 21 boys with 47,XYY and 93 boys with 47,XXY (KS), age 4-17 years, and 36 age-matched control boys. Both the XYY and KS groups performed less well, on average, than the controls on tests of general cognitive ability, achievement, language, verbal memory, some aspects of attention, and executive function, and motor function. The boys with XYY on average had more severe and pervasive language impairment, at both simple and complex levels, and the boys with KS on average had greater motor impairment in gross motor function and coordination, especially in running speed and agility.
The results from these large XYY and KS cohorts have important neurocognitive and educational implications. From the neurocognitive standpoint, the presenting findings afford an opportunity to gain insights into brain development in boys with XYY and those with KS. From the educational standpoint, it is critical that boys with XYY or KS receive appropriate educational interventions that target their specific learning challenges. These findings also provide important information for counseling clinicians and families about these disorders.
The developmental and clinical aspects in the literature on triple X syndrome are reviewed. Prenatal diagnosis depends on karyotyping. The incidence is 1 of 1000 females. At birth, 47,XXX girls have a lower mean birth weight and a smaller head circumference. Triple X diagnosis was not suspected at birth. The maternal age seems to be increased. Toddlers with triple X syndrome show delayed language development. The youngest girls show accelerated growth until puberty. EEG abnormalities seem to be rather common. Many girls show motor-coordination problems and auditory-processing disorders are not rare. Scoliosis is probably more common in adolescent cases. The IQ levels are 20 points below that of controls, and verbal IQ is lowest. The girls struggle with low self-esteem and they need psychological, behavioural and educational support. They perform best in stable families. After leaving school they seem to feel better. In adults, premature ovarian failure seems to be more prevalent than in controls. MRIs of the brain seem to show decreased brain volumes. The 47,XXX women most often find jobs that reflect their performance abilities. Psychotic illness seems to be more prevalent in triple X adult women than in controls. Psychotic disorders respond well to psychotropic drugs. Triple X adults suffer more frequently from cyclothymic and labile personality traits. Research on triple X syndrome may yield more insight into brain and behaviour relations, developmental psychopathology, auditory-processing disorders, EEG disorders, personality and psychotic disorders, etc.
Turner syndrome is caused by haploinsufficiency of the short arm of X-chromosome, and is usually diagnosed by karyotyping. This procedure is time-consuming, expensive and unfeasible for population screening. We propose molecular detection of 45XO Turner patients based on the ability of HpaII, a methylation sensitive endonuclease, to induce the cleavage of non-methylated DNA in the active X-allele. Genomic DNA was obtained from 22 patients with Turner syndrome confirmed by karyotype (45XO, N = 18; 45XO/46XX, N = 4). After digestion, DNA was amplified with primers directed to exon 1 of the androgen receptor (AR) gene and to the GAPDH control gene. Normal control females or mosaic patients, with a second methylated X-chromosome, escaped from HpaII digestion and produced a band corresponding to AR gene amplification. 45XO patients have just one active non-methylated X-chromosome, completely digested by HpaII, thus preventing the amplification of the AR gene. Three of the 45XO cases gave amplified bands, suggesting low-frequency mosaicisms that are not detected by karyotyping. Compared to classical karyotype studies for the detection of 45XO Turner patients, this new molecular method is simpler, faster and less expensive.
The age at diagnosis of 242 girls with Turner syndrome (TS) treated in Belgium with growth hormone between 1991 and 2002 was evaluated. The median (range) age at diagnosis was 6.6 (0-18.3) years. Patients with 45,X karyotype were diagnosed earlier than patients with other karyotypes. Compared to a previous survey, performed on 100 patients 12 years earlier, more patients were diagnosed during infancy and childhood, and less during adolescence. However, in 22% of the girls the diagnosis was made after the age of 12 years; these girls showed the largest height deficit. As early diagnosis has several potential advantages we recommend that a cytogenetic analysis should be considered in all girls with unexplained short stature with height below -2 SD of the mean for age or below the parent specific lower limit of height.
An extra X chromosome in males (XXY), known as Klinefelter syndrome, is associated with characteristic physical, cognitive, and behavioral features of variable severity. The objective of this study was to examine possible neuroanatomical substrates of these cognitive and behavioral features during childhood and adolescence.
MRI brain scans were acquired for 42 XXY and 87 healthy XY age-matched control males. We compared these 2 groups on regional brain volumes and cortical thickness.
Total cerebral volume and all lobar volumes except parietal white matter were significantly smaller in the XXY group, whereas lateral-ventricle volume was larger. Consistent with the cognitive profile, the cortex was significantly thinner in the XXY group in left inferior frontal, temporal, and superior motor regions.
The brain-imaging findings of preferentially affected frontal, temporal, and motor regions and relative sparing of parietal regions are consistent with observed cognitive and behavioral strengths and weaknesses in XXY subjects.
Objective:
Neurodevelopmental concerns in males with sex chromosome aneuploidy (SCA) (XXY/Klinefelter syndrome, XYY, XXYY) include symptoms seen in autism spectrum disorder (ASD), such as language impairments and social difficulties. We aimed to: (1) evaluate ASD characteristics in research cohorts of SCA males under DSM-IV compared to DSM-5 criteria, and (2) analyze factors associated with ASD diagnoses in SCA.
Methods:
Evaluation of participants with XXY/KS (n=20), XYY (n=57) and XXYY (n=21) included medical history, cognitive/adaptive testing, Social Communication Questionnaire, Social Responsiveness Scale, Autism Diagnostic Observation Schedule, Autism Diagnostic Interview-Revised, and DSM ASD criteria. Clinical impressions of ASD diagnostic category using the ADOS and DSM-IV criteria were compared to ADOS-2 and DSM-5 criteria. T-tests compared cognitive, adaptive, SES and prenatal vs. postnatal diagnoses between ASD and no ASD groups.
Results:
ASD rates in these research cohorts were 10% in XXY/KS, 38% in XYY, and 52% in XXYY using ADOS-2/DSM-5, and were not statistically different compared to DSM-IV criteria. In XYY and XXYY, the ASD group had lower verbal IQ and adaptive functioning compared to those without ASD. Many children without ASD still showed some social difficulties.
Conclusion:
ASD rates in males with SCA are higher than reported for the general population. Males with Y chromosome aneuploidy (XYY and XXYY) were 4.8 times more likely to have a diagnosis of ASD than the XXY/KS group, and 20 times more likely than males in the general population (1 in 42 males, CDC 2010). ASD should be considered when evaluating social difficulties in SCA. Studies of SCA and Y-chromosome genes may provide insight into male predominance in idiopathic ASD.
Polysomy of the X chromosome is a very rare disorder, and little information is available in the literature. Tetrasomy X was first reported in 1961 and only approximately 60 cases have been reported. Herein, we reported a 5-year-old girl with tetrasomy X, who presented to our clinics because of "short stature". She was born to a G2P2 mother at 39 weeks of gestation with a birth weight of 3.5 kg. She started walking at 16 months of age, and speaking at 18 months. She had syndactyly in both hands and patent ductus arteriosus (0.7 cm), which were corrected by surgery soon after birth and at 7 months of age, respectively. She also had a history of epilepsy for 3 years with 4 episodes of convulsion but none in the past two years, and depakine was administered till now. She was apt to get pneumonia. She was 105 cm in height and 13 kg in weight, showing a coarse face with ocular hypertelorism and epicanthus. She presented with female external genitalia with Tanner I breast and external genitalia development. Her pelvic ultrasound showed immature uterus and ovarian. Intelligence quotient test revealed low intellectual functioning (IQ: 51). Cytogenetic investigation revealed a karyotype of 48,XXXX. These data showed that in females with intellectual disabilities, abnormal height, microcephaly, skeletal and limb anomalies, and congenital heart defects, 48,XXXX karyotype should be considered although it is an extremely rare entity.
A 20-year follow-up study of 50 hypogonadal males has been made. Of these 34 had Klinefelter's syndrome with the karyotype 47,XXY and 16 had the karyotype 46,XY. These males have been examined at mean ages of 27 and 37 and in the present study at a mean age of 47. At the first examination the following conditions were found in the Klinefelter males to a significantly higher degree than in the hypogonadal males with 46,XY: immaturity, below average school performance, few or no friends, previous mental illness, little energy and initiative, few or no spare time interests, occupation as an unskilled labourer. Psychological testing showed a full scale IQ of 103 in the Klinefelter males and 115 in the hypogonadal males. The follow-up studies have shown that in spite of these findings the Klinefelter males have managed far better than could have been expected at the time of the first investigation. The improvement in a number of conditions such as mental health, working capacity, social adjustment, relations with other people, and activity level was considerable between the ages of 27 and 37. The present examination shows a further improvement at the age of 47 with the only significant difference between the Klinefelter males and the hypogonadal males with 46,XY being a higher frequency of single Klinefelter males. The present examination also showed that there was no significant difference between the two groups in occupation, working capacity, social adjustment, mental and physical disorders or criminality. The results of the examination at the mean age of 27 would probably have been considerably more favourable for the Klinefelter males if diagnosis had been made in childhood, and information, counselling, support and hormone treatment had been given from an early age. The fact that the great majority of the Klinefelter males have managed quite well in spite of this and that no remarkable differences were found between them and a control group is of great importance for genetic counsellers, especially for prenatal counsellers. Up until now, in 75% of cases in which sex chromosome abnormalities, including Klinefelter's syndrome, have been diagnosed prenatally in Denmark abortion has been induced. We believe this is mainly due to insufficient information about the many positive aspects of the development of individuals with sex chromosome abnormalities.
To describe auxologic, physical, and behavioral features in a large cohort of males with 47,XYY (XYY), ages newborn to young adult.
This is a cross-sectional descriptive study of male subjects with XYY who were evaluated at 1 of 2 specialized academic sites. Subjects underwent a history, physical examination, laboratory testing, and cognitive/behavioral evaluation.
In 90 males with XYY (mean age 9.6 ± 5.3 years [range 0.5-36.5]), mean height SD was above average (1.0 ± 1.2 SD). Macrocephaly (head circumference >2 SD) was noted in 28/84 (33%), hypotonia in 57/90 (63%), clinodactyly in 47/90 (52%), and hypertelorism in 53/90 (59%). There was testicular enlargement for age (>2 SD) in 41/82 (50%), but no increase in genital anomalies. No physical phenotypic differences were seen in boys diagnosed prenatally vs postnatally. Testosterone, luteinizing hormone, and follicle stimulating hormone levels were in the normal range in most boys. There was an increased incidence of asthma, seizures, tremor, and autistic spectrum disorder (ASD) compared with the general population rates. Prenatally diagnosed boys scored significantly better on cognitive testing and were less likely to be diagnosed with ASD (P < .01).
The XYY phenotype commonly includes tall stature, macrocephaly, macroorchidism, hypotonia, hypertelorism, and tremor. Physical phenotypic features were similar in boys diagnosed prenatally vs postnatally. Prenatal diagnosis was associated with higher cognitive function and less likelihood of an ASD diagnosis.
Background: Supernumerary sex chromosome aneuploidies (X/Y-aneuploidies), the presence of extra X and/or Y chromosomes, are associated with heightened rates of language impairments and social difficulties. However, no single study has examined different language domains and social functioning in the same sample of children with tri-, tetra-, and pentasomy X/Y-aneuploidy. The current research sought to fill this gap in the literature and to examine dosage effects of X and Y chromosomes on language and social functioning.
Methods: Participants included 110 youth with X/Y-aneuploidies (32 female) and 52 with typical development (25 female) matched on age (mean ∼12 years; range 4–22) and maternal education. Participants completed the Wechsler intelligence scales, and parents completed the Children’s Communication Checklist-2 and the Social Responsiveness Scale to assess language skills and autistic traits, respectively.
Results: Both supernumerary X and Y chromosomes were related to depressed structural and pragmatic language skills and increased autistic traits. The addition of a Y chromosome had a disproportionately greater impact on pragmatic language; the addition of one or more X chromosomes had a disproportionately greater impact on structural language.
Conclusions: Given that we link extra X chromosomes with structural language impairments and an extra Y chromosome with pragmatic language impairments, X/Y-aneuploidies may provide clues to genetic mechanisms contributing to idiopathic language impairment and autism spectrum disorders.
Klinefelter syndrome (KS) is the most common sex chromosome disorder and a major cause of male infertility. In adult patients, serum inhibin B and anti-Mullerian-hormone (AMH) are undetectable, testosterone secretion is often impaired, and the tubules are depleted of germ cells. Before puberty, inhibin B, AMH, and testosterone levels are within the normal range.
Sertoli and Leydig cell secretions, including insulin-like peptide-3 (INSL3), were evaluated in infants with nonmosaic XXY karyotype to assess testicular function soon after birth.
The study was conducted in four University Pediatric Departments from the United States and France.
Sixty-eight prenatally diagnosed infants aged 2-750 d were enrolled.
Serum FSH, LH, inhibin B, AMH, and INSL3 were measured by immunoassay, and testosterone was measured by tandem mass-spectrometry.
In infants with KS, INSL3 levels transiently increased at 2-3 months of age and were significantly correlated with testosterone (Spearman r = 0.57) and LH (Spearman r = 0.73) levels. They did not differ from controls. Testosterone levels were within the normal range, but most of them were below the median of controls. Inhibin B and AMH levels were also within normal range. Inhibin B was correlated with FSH (Spearman r = 0.49). AMH was not correlated with FSH or testosterone. FSH levels were above normal in 25% of patients, despite normal inhibin B levels.
In infants with KS, Leydig cells are normally sensitive to the LH proliferative effect. In contrast, the Sertoli cell sensitivity to FSH is questionable, which may be prophetic of the postpubertal Sertoli cell resistance to FSH.
Turner syndrome is a disorder that has distinct clinical features and has karyotypic aberrations with loss of critical regions of the X chromosome. Several clinical guidelines on the diagnosis and management of patients with Turner syndrome have been published, but there is relatively little on the laboratory aspects associated with this disorder. This disease-specific laboratory guideline provides laboratory guidance for the diagnosis/study of patients with Turner syndrome and its variants. Because the diagnosis of Turner syndrome involves both a clinical and laboratory component, both sets of guidelines are required for the provision of optimal care for patients with Turner syndrome.
Klinefelter syndrome (47,XXY) was initially described in the context of its endocrinologic and physical features; however, subsequent studies have revealed specific impairments in verbal skills and social functioning. Males with sex chromosomal aneuploidies are known to have variability in their developmental profile with the majority presenting with expressive language deficits. As a consequence of language delays, they have an increased likelihood of language-based learning disabilities and social-emotional problems that may persist through adulthood. Studies on males with 47,XXY have revealed unique behavioral and social profiles with possible vulnerability to autistic traits. The prevalence of males with more than one extra sex chromosome (e.g., 48,XXYY and 48,XXXY) and an additional Y (e.g., 47,XYY) is less common, but it is important to understand their social functioning as it provides insight into treatment implications.
A 37-year-old woman, gravida 1, seeks prenatal care at 8 weeks' gestation. Her family history and medical history are unremarkable. What would you advise regarding her risk of fetal chromosomal abnormalities such as Down's syndrome and her options for prenatal screening and diagnosis?
An international group of clinicians working in the field of dysmorphology has initiated the standardization of terms used to describe human morphology. The goals are to standardize these terms and reach consensus regarding their definitions. In this way, we will increase the utility of descriptions of the human phenotype and facilitate reliable comparisons of findings among patients. Discussions with other workers in dysmorphology and related fields, such as developmental biology and molecular genetics, will become more precise. Here we introduce the anatomy of the craniofacies and define and illustrate the terms that describe the major characteristics of the cranium and face.
One hundred and ten patients with abnormal karyotypes who were referred to the Department of Medical Genetics with the possible diagnosis of Turner syndrome were reviewed. The frequency of chromosomal abnormalities and clinical findings in the different chromosomal types are summarized.
Development of 11 girls (ages 2-10 years) with 47,XXX karyotype identified in a newborn survey is compared with eight girls having a mosaic sex chromatin pattern and with the normal siblings of each group. Delay in early motor development and speech, a mild intellectual deficit, and disturbance in interpersonal relationships occurred in one-third of the index cases, a higher frequency than in the comparison groups. two-thirds were considered normal and adequately adjusted. No consistent phenotype was found.
Of 25,000 Danish schoolboys, aged 15-16 years, 16 were found to have previously undiagnosed Klinefelter's syndrome. Comparison of these boys with normal controls indicated that on average these subjects had increased height, reduced weight, impaired hearing, slightly lowered intelligence, poor school performance, increased incidence of psychological consultation and lowered sexual activity compared with their peers.
A 13-year incidence study of sex chromosome abnormalities in Arhus, Denmark of 34,910 newborn children showed that 1 per 448 had a sex chromosome abnormality. The incidences of the most common sex chromosome abnormalities were Klinefelter syndrome, 1 per 576 boys; XYY, 1 per 851 boys; triple X, 1 per 897 girls; Turner syndrome, 1 per 2130 girls. Follow-up of children with autosomal abnormalities is not included in this study. None of the 78 surviving children with sex chromosome abnormalities was mentally retarded. All children above school age attended regular schools. Seventy-seven percent of Klinefelter, triple X, and XYY children aged 15-19 had received remedial teaching, 29% were receiving remedial teaching at the last follow-up, 32% had been in special classes at a regular school due to learning problems, and 24% were still in such classes at the last time of follow-up. There was no increased frequency of criminal activity or behavior disorders, nor was there any increased frequency of mental or physical disorders. The distribution of planned training or occupation for the 25 youths with sex chromosome abnormalities between 15 and 19 years of age was similar to that of their sibs. Testosterone undecanoate treatment has been given to Klinefelter boys from puberty and growth hormone treatment to Turner girls from the age of 7, and very small doses of estrogen were given to these girls from around the age of 12 when FSH was increasing to postmenopausal levels. Prevention or reduction of deviations in mental development from the normal range in children with sex chromosome abnormalities is possible if educational and social resources are available and the parents are well informed and counseled regularly. Information in Denmark has been given in part by publishing four booklets about triple X, XYY, Turner, and Klinefelter syndrome. Information, support, and stimulation to self-help have, to a certain extent, been given through contact groups. Parents having a child with a sex chromosome abnormality need information, counseling, and assistance. The type and magnitude of this assistance depend on the individual child, the specific sex chromosome abnormality, and the parents' own resources, psychologically, socially, and otherwise.
The present study is the psychological part of a comprehensive study of male patients with the XYY syndrome. Findings from the studies indicate that the intelligence level in XYY males is within the normal range. Special traits characterized the cognitive function, most clearly manifested in a high subtest scatter. The lack of persistence and the lack of social reflection seemed to be caused by a low anxiety tolerance that was manifest in all patients, apparently originating in the presence of sexual conflicts as well as in conflicts around contact. With respect to emotionality, it seemed that a connection could be seen between reliance upon repression and more openly impulsive reactions, whereas the patients whose defences were evasion or withdrawal showed restraint and a tendency to more explosive reactions.
The incidence of gross chromosomal abnormality was measured in a large (4500), relatively unbiased sample of New Haven infants
born during 1 year. The frequency of infants with abnormal chromosomal constitutions was 0.5 percent. For mothers over age
34, 1.5 percent of newborns were chromosomally abnormal. Only one in four of these infants could have been detected by phenotypic
criteria alone. Methods are discussed whereby this fraction of the newborn population might be detected and possibly reduced.
Two patients with 47,XXX karyotypes and premature ovarian failure are described. Both presented with episodes of amenorrhea, elevated levels of circulating follicle-stimulating hormone and luteinizing hormone, and decreased estrogen concentrations. However, evidence of follicular activity existed in both cases. Why some women with 47,XXX karyotypes suffer from premature ovarian failure and why others have normal fertility and normal lengths of reproductive function is not known. Reports of immunologic disorders in patients with the triple-X syndrome and data showing that control of the lymphocyte may be related to the X chromosome point to a possible link between premature ovarian failure in 47,XXX women and immunologic abnormalities.
This double-blind, controlled study of XYY and XXY men found in a birth cohort of 4,591 tall men born in Copenhagen assessed evidence of delinquent and aggressive behavior and explored the role of hormonal determinants in the behavioral and psychological differences noted among groups. Information from social records, a structured psychological interview, and projective tests did not support the notion that men with sex chromosome anomalies are particularly violent or aggressive. Hormonally, XYY men had significantly higher concentrations of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) than matched control groups. In contrast, XXY men had higher levels of LH, FSH, and prolactin, but low concentrations of testosterone. There was a significantly positive relation among all subjects as well as XY controls alone between plasma testosterone level and evidence of criminal convictions. A proportionate increase in testosterone levels was noted when subjects were divided into nondelinquents, delinquents without violent convictions, and delinquents with violent convictions. The relation between testosterone level and criminal behavior was not reflected in measures of aggression derived from the psychological interview and projective tests. There was no specific evidence that testosterone is a mediating factor in the criminal behavior of XYY men.
Children with sex chromosome abnormalities (SCA) are known to be at risk for developmental delays. These risks were identified 2 decades ago by seven international research groups who prospectively followed children ascertained after birth. Subsequently, some of these investigators suggested the course of prenatally identified children with SCA may be different from children in earlier studies. The first such evidence was published by Robinson et al. [1992: Am J Med Genet 44:365-368], who compared 20 prenatally diagnosed children to the original postnatally diagnosed cohort. The following report presents an update and expansion of that research and includes 51 children and adolescents prenatally diagnosed with SCA, now 7-18 years of age. Results confirm that this cohort of prenatally diagnosed children has a milder developmental course than children ascertained postnatally. The study provides new information to health professionals counseling families faced with prenatal diagnosis of SCA.
Most children with Turner's syndrome are under the care of specialists. It has been proposed that adults should also be followed in multidisciplinary specialty clinics. We believe, on the basis of our own experience, that most affected women can best be served by their primary care practitioners, with the use of informed judgment about the need for referral to specialists. Although these women have substantial health concerns, their care for the most part falls under the standard repertoire of primary care, and continued follow-up in specialty care centers may inhibit their integration into society and foster a sense of ill-being. Support groups for patients with Turner's syndrome and their families (listed in the Appendix) can be a source of valuable information.
This paper studies brain morphometry variation associated with XXY males (Klinefelter's syndrome) by using an automated whole-brain volumetric analysis method. The application to 34 XXY males and 62 normal male controls reveals pronounced volume reduction in the brains of XXY males, relative to the brains of normal controls, localized at the insula, temporal gyri, amygdala, hippocampus, cingulate, and occipital gyri. Most of these statistically significant regions are in the gray matter structures, with the exception of one cluster of atrophy involved in white matter structure, i.e., right parietal lobe white matter. Compared to previous findings documented in the literature, our findings provide a better spatial localization of the affected regions. In addition to the reduction of local volume, overall enlargement of ventricles and overall volume reduction of both white matter and gray matter are also found in XXY males.
Males with an extra-X chromosome (Klinefelter's syndrome) frequently, although not always, have an increased prevalence of psychiatric disturbances that range from attention deficit disorder in childhood to schizophrenia or severe affective disorders during adulthood. In addition, they frequently have characteristic verbal deficits. Thus, examining brain magnetic resonance imaging (MRI) scans of these individuals may yield clues to the influence of X chromosome genes on brain structural variation corresponding to psychiatric and cognitive disorders. Eleven adult XXY and 11 age matched XY male controls were examined with a structured psychiatric interview, battery of cognitive tests, and an MRI scan. Ten of eleven of the XXY men had some form of psychiatric disturbance, four of whom had auditory hallucinations compared with none of the XY controls. Significantly smaller frontal lobe, temporal lobe, and superior temporal gyrus (STG) cortical volumes were observed bilaterally in the XXY men. In addition, diffusion tensor imaging (DTI) of white matter integrity resulted in four regions of reduced fractional anisotropy (FA) in XXY men compared with controls, three in the left hemisphere, and one on the right. These correspond to the left posterior limb of the internal capsule, bilateral anterior cingulate, and left arcuate bundle. Specific cognitive deficits in executive functioning attributable to frontal lobe integrity and verbal comprehension were noted. Thus, excess expression of one or more X chromosome genes influences both gray and white matter development in frontal and temporal lobes, as well as white matter tracts leading to them, and may in this way contribute to the executive and language deficits observed in these adults. Future prospective studies are needed to determine which gene or genes are involved and whether their expression could be modified with appropriate treatments early in life. Brain expressed genes that are known to escape inactivation on extra-X chromosomes would be prime candidates.
One case of 48, XXXX
- F Lin
Lin F. One case of 48, XXXX. Chin J Med Genet. 1996, 13:
122.
Y chromosome in Turner syndrome: a review of the literature
- R M Oliveira
- I T Verreschi
- M V Lipay
- L P Eca
- A D Guedes
- B Blanco
Oliveira R.M., Verreschi I.T., Lipay M.V., Eca L.P., Guedes
A.D., Blanco B. Y chromosome in Turner syndrome: a
review of the literature. Sao Paulo Med J. 2009, 127 (6):
373-378.
A case-control study of brain structure and behavioral characteristics in 47, XXX syndrome
- K Rhoshel
- M J Lenroot
Rhoshel K., Lenroot M.J. A case-control study of brain
structure and behavioral characteristics in 47, XXX
syndrome. Genes Brain and Behav. 2014, 20: 841-849.