International investigation of neurocognitive and behavioral phenotype in 47,XXY (Klinefelter syndrome): Predicting individual differences

47,XXY (KS) occurs in 1:650 male births, though less than 25% are ever identified. We assessed stability of neurocognitive features across diverse populations and quantified factors mediating outcome. Forty‐four boys from the Netherlands (NL) and 54 boys from the United States (US) participated. The Wechsler Intelligence Scales assessed intellectual functioning; the ANT program evaluated cognitive function; and the CBCL assessed behavioral functioning. ANOVA was used for group comparisons. Hierarchical regressions assessed variance explained by each independent variable: parental education, timing of diagnosis, testosterone, age, and nationality. Parental education, timing of diagnosis, and hormonal treatment all played an important role in neurocognitive performance. The observed higher IQ and better attention regulation in the US group as compared to the NL group was observed with decreased levels of behavioral problems in the US group. Cognitive measures that were different between the NL and US groups, i.e., attention regulation and IQ scores, were also significantly influenced by external factors including timing of diagnosis, testosterone treatment, and parental education. On the ANT, a cognitive phenotype of 47,XXY was observed, with similar scores on 9 out of the 10 ANT subtests for the NL and US groups. This study lays additional features to the foundation for an algorithm linking external variables to outcome on various neurodevelopmental measures.

     

Behavioral phenotype of 49,XXXXY syndrome: Presence of anxiety‐related symptoms and intact social awareness

49,XXXXY is a rare X and Y chromosome variation that occurs in 1:85,000 to 1:100,000 live male births and is notable for variable motor, speech, and behavioral deficits. Case studies have described boys with this disorder as shy, impulsive, and aggressive with low frustration tolerances; however, previous studies have been limited due to cohort size. This study reports on the largest cohort of boys with 49,XXXXY to date with an emphasis on the prevalence of anxiety‐related symptoms and sociability from preschool to adolescence. The Child Behavior Checklist, Behavior Rating Inventory of Executive Function, 2nd edition, and Social Responsiveness Scale, 2nd edition were completed by parents on a cohort of 69. The cohort demonstrated deficits in social cognition and communication beginning in preschool, however, presented with consistent social awareness and motivation for social activities not previously appreciated in this disorder. In addition, signs of anxiety presented during preschool years and increased in severity with age, particularly in internalizing problems. Boys with 49,XXXXY presented with wide behavioral variability across all ages and domains. Further research into the potential influences of culture, birth order, biological treatment, and frequency of services is needed to better define the behavioral phenotype of children with this disorder.     

Musculoskeletal anomalies in a large cohort of boys with 49, XXXXY

49, XXXXY is a rare aneuploidy and variant of Klinefelter syndrome, occurring in 1 per 80,000–100,000 live births. We present a cohort of 40 affected males, focusing on musculoskeletal problems. Subjects were participants in an annual 49er family support group meeting. Children were examined in a multidisciplinary clinic by a pediatric neurologist and geneticist, a pediatric orthopedist, a neurodevelopmentalist, and two physical therapists. The patient data were collected from this clinic from 2004 to 2012. All patients were required to have karyotypes that confirmed the presence of XXXXY. There was a high prevalence of musculoskeletal disorders, particularly hypotonia (34 patients [85%]), radioulnar synostosis (30 [75%]), pes planus (26 [65%]), asymmetric hip rotation (27 [67.5%]), and clinodactyly (24 [60%]). Other, less common lower-extremity disorders, included, 5 patients (12.5%) with unilateral club foot, 5 boys (12.5%) with pes cavus, 10 patients (25%) genu valgum and 2 children with genu varus (5%). To our knowledge, this is the first large cohort of boys with 49, XXXXY that focuses on musculoskeletal disorders. There was an increased incidence of hypotonia, clubfoot, avascular necrosis of the femoral head, radioulnar synostosis, and pes planus compared to the normative population. Boys with 49, XXXXY would benefit from multidisciplinary evaluations, particularly from pediatric orthopedists, physical therapists, neurologists, and geneticists for appropriate medical care. © 2013 Wiley Periodicals, Inc.     

The incidence of anxiety symptoms in boys with 47,XXY (Klinefelter syndrome) and the possible impact of timing of diagnosis and hormonal replacement therapy

47,XXY (Klinefelter syndrome) is the most common X and Y chromosomal variation (1:660 males). The incidence of anxiety disorders and the impact of hormonal replacement therapy (HRT) is not well understood. Child Behavior Checklist and Screen for Childhood Anxiety Related Emotional Disorders were completed by parents of 80 boys with 47,XXY. Forty received HRT prior to 10 years of age while 40 did not. HRT (22.5%) received early hormonal treatment prior to 18 months. About 32.5% received hormone booster treatment between 5 and 10 years. The remaining 42.5% received both. There were fewer reported social (p = .015), thought (p = .012), and affective problems (p = .048) in treated boys when compared to untreated. Boys with both treatments demonstrated fewer symptoms on anxious/depressed scale (p = .001) compared to those with early treatment only. Within the treated group, prenatally diagnosed showed fewer indications of anxiety problems (p = .02) than their postnatal counterparts. This comparative, cross‐sectional study expands previous findings on the possible positive effect of HRT in boys with 47,XXY. Anxiety disorders appear to be a penetrant aspect of the 47,XXY phenotype. Further investigation is warranted to explore the relationship between biological treatment and individual responses to HRT to develop more personalized and precise medicine.     

Clinical report of 8 patients with 49,XXXXY syndrome: Delineation of the facial gestalt and depiction of the clinical spectrum

49,XXXXY syndrome is a rare sex chromosome aneuploidy syndrome. Cognitive impairment with expressive language deficits in combination with developmental and speech dyspraxia are cardinal symptoms. Testicular insufficiency becomes apparent during adolescence. Neurological, musculoskeletal, genital, orthodontic and immunological anomalies are common and a higher incidence of congenital malformations has been described. Here we show the evolving clinical and facial phenotype of eight boys and men with 49,XXXXY, demonstrating an increasingly perceptible distinct facial gestalt over time. In addition, almost all patients had muscular hypotonia, radioulnar synostosis, white matter anomalies, fifth-finger clinodactyly, recurrent respiratory infections in early childhood and teeth anomalies. IQ scores ranged between 40 and 70. Though many boys showed short stature at some point in early childhood, most outgrew it. As more long term data of boys and men with 49,XXXXY become available, parents of affected boys can be counseled more specifically as to the expected course and spectrum of this rare chromosomal disorder. Moreover, the multidisciplinary support can be optimized und unnecessary diagnostics avoided.     

Sleep Problems and Life Satisfaction as Predictors of Health in Men with Sex Chromosome Aneuploidies

More knowledge is needed about men with sex chromosome aneuploidies (SCA). We present self-reported data from 53 men with SCA (M_age = 36.8 years, SD = 12.3, range 19–67). The Health Survey–Short Form (SF-36) measured eight health domains (physical functioning, role-physical, role-emotional, vitality, emotional health, social functioning, pain, general health). The Pittsburgh Sleep Quality Index measured sleep problems. The Personal Wellbeing Index measured satisfaction with eight life domains. Compared to norms, SCA reported poorer health (mean d = ?0.80) and more sleep problems (mean d = ?0.85). Differences between SCA and norms on personal well-being were small, except lower health satisfaction in SCA (d = ?1.06). Seven of eight regression models predicting the SF-36 domains from life satisfaction and sleep problems were significant (explained variance 12.2% to 46.2%), except physical functioning (ns). Clinical assessment/intervention for a broad range of health and sleep problems is indicated for men with SCA.     

Parental origin of chromosomal non-disjunction in a 49,XXXXY male using recombinant-DNA techniques

We have analyzed the origin, in a patient with 49,XXXXY, of the four X-chromosomes by means of recombinant DNA techniques. We found a maternal origin of the four X-chromosomes due to non-disjunctions in the first and second meiotic divisions.     

Positive effects of short course androgen therapy on the neurodevelopmental outcome in boys with 47,XXY syndrome at 36 and 72 months of age

The effects of early androgen treatment on neurodevelopmental performance in pre‐pubertal boys with 47,XXY have not been well investigated. The influence of hormones on brain development in humans suggests that a positive effect on neurodevelopmental outcome in young boys with XXY may be plausible with hormone replacement therapy. The aim of the study was to investigate retrospectively if an early course of androgen treatment (three injections of testosterone enanthate, 25 mg, each) had an impact on specific domains of neurodevelopmental function in boys with 47,XXY at 36 and 72 months of age. One hundred one boys with a karyotype of 47,XXY had neurodevelopmental assessments. The retrospective chart review resulted in one group (n = 34) who had received androgen treatment during infancy and the second group was untreated (N = 67). Statistical analysis was completed to determine if there was a positive effect from treatment observed at 36 and at 72 months on multiple domains of development. There were significant differences in multiple cognitive domains in the group who received androgen treatment, including multiple measures of language, intellectual, and neuromotor skills. Improved function was observed in neurodevelopmental outcome in boys with 47,XXY at 36 and 72 months who had been treated with a short course of androgen treatment in infancy. Continued research is underway to expand our understanding of the relationship of androgen, brain function, and neurobehavioral and neurodevelopmental outcome in boys with 47,XXY. © 2013 Wiley Periodicals, Inc.     

Evidence of skewed X‐chromosome inactivation in 47,XXY and 48,XXYY Klinefelter patients

Klinefelter (47,XXY) syndrome occurs in approximately 1:800 male births and accounts for about 10‐20% of males attending infertility clinics. Recent studies have shown no obvious phenotypic differences between subjects in which the extra X‐chromosome is of paternal or maternal origin; however, a minority of Klinefelter patients are adversely affected clinically and intellectually to an exceptional level, and the underlying basis of this phenotypic variation is not known. We hypothesize that skewed X‐inactivation and possibly parental origin of the X‐chromosomes is involved. In this study, we determined parental origin and inactivation status of the X‐chromosomes in 17 cytogenetically confirmed 47,XXY cases, two 48,XXYY cases and one mosaic 46,XY/47,XXY case. Eight highly polymorphic markers specific to the X‐chromosome and the polymorphic human androgen‐receptor (HUMARA) methylation assay were used to determine the parental origin and X‐inactivation status of the X‐chromosomes, respectively. Overall, 17 cases were fully informative, enabling parental origin to be assigned. In 59% of cases, both X‐chromosomes were of maternal origin (X^m); in the remaining 41%, one X was of maternal (X^m) and one was of paternal origin (X^p). In 5 of 16 (31%) cases informative at the HUMARA locus, skewed X‐inactivation was observed as defined by greater than 80% preferential inactivation involving one of the two X‐chromosomes. The two 48,X^mX^pYY cases both showed preferential paternal X‐chromosome (X^p) inactivation. Three 47,X^mX^mY cases also showed preferential inactivation in one of the two maternal X‐chromosomes. These results suggest that skewed X‐inactivation in Klinefelter (47,XXY and 48,XXYY) patients may be common and could explain the wide range of mental deficiency and phenotypic abnormalities observed in this disorder. Further studies are warranted to examine the role of X‐inactivation and genetic imprinting in Klinefelter patients. © 2001 Wiley‐Liss, Inc.     

Sex chromosome aneuploidy and anthropometry: A new proportionality assessment using the phantom stratagem

Reported anthropometric data on 121 subjects with 47, XYY, 47,XXY, 47,XXX, and 45,X aneuploidies were compared to those from 578 male and female control subjects by use of a single, unisex reference person (“phantom”). Subjects and controls were geometrically scaled to a standard stature of 170.18 cm, thus eliminating variance due to height. Deviations of anthropometric variables from specified phantom values were expressed as standard z-scores. By comparing z-scores of individual aneuploidy classes with those of their controls, further differences in proportionality came to light. The stratagem disclosed a systematic proportionality pattern between subjects and controls which appeared to be related to each specific sex chromosome aneuploidy. The phantom stratagem for proportional growth assessment appears to merit further use in genetic investigations where individual differences in size and shape confound the analysis of anthropometric data.     

Infant with mos45,X/46,XY/47,XYY/48,XYYY: Genetic and clinical findings

We describe an infant with mos45,X/46,XY/47,XYY/48,XYYY who presented with ambiguous genitalia. Her phenotype was also remarkable for minor ear and eye anomalies and coarctation of the aorta with bicuspid aortic valve. Laparoscopy revealed bilateral Fallopian tubes and a left infantile testis with epididymis. Chromosomal analyses of blood, skin, aorta, right Fallopian tube, and left gonadal tissue showed mos45,X/46,XY/47,XYY/48,XYYY. The 46,XY cell line was identified with routine trypsin-Giemsa banding only in cultured cells from an aortic biopsy. Fluorescence in-situ hybridization (FISH) was utilized to identify the presence of 46,XY cells in other tissues. The clinical manifestations of this patient are discussed and compared with those of similar cases of Y chromosome aneuploidy. To our knowledge, this is the first report of a patient with this unusual karyotype. © 1995 Wiley-Liss, Inc.     

Application of fluorescent in situ hybridization with X and Y chromosome specific probes to buccal smear analysis

Conventional X- and Y-chromatin and fluorescent in situ hybridization (FISH) analysis based on X- and Y-chromosome specific probes were conducted from buccal smear, on 15 normal males, 15 normal females, and 9 cases suspected of sex chromosome anomalies. The proportion of X- and Y-chromatin in normal females and males was 12% ± 3% and 51.5% ± 4.9%, respectively, by the conventional X- and Y-chromatin procedure. The CEP-X/Y analysis by FISH for the same specimens provided a proportion of 98.8% ± 0.7% cells with XX signals in the normal females and 99.8% ± 0.4% cells with XY signals in the normal males. The FISH method was superior to the conventional procedure in nine cases suspected of sex chromosome anomalies, including one case of mosaicism. The results of CEP-X/Y will sometimes be false; it will not detect structural anomalies of sex chromosomes, and it is not intended to detect low level mosaicism. However, the test is useful for rapid screening of sex chromosome aneuploidy at a fraction of the cost for chromosome analysis. The FISH test is also appropriate to detect tissue specific sex chromosome mosaicism, especially if it is relatively high. This FISH test is best used as an adjunct to chromosome analysis whenever possible. © 1996 Wiley-Liss, Inc.     

Comparison of aneuploidies of chromosomes 21, X,and Y in the blood lymphocytes and sperm of workers exposed to benzene

Benzene is a primary industrial chemical and a ubiquitous environmental pollutant that causes human leukemia and maybe other malignancies. Occupational exposure to benzene has been associated with increased chromosomal aneuploidies in blood lymphocytes and, in separate studies, in sperm. However, aneuploidy detection in somatic and germ cells within the same benzene‐exposed individuals has never been reported. To compare aneuploidies in blood lymphocytes and sperm within the same individuals exposed to benzene, a cross‐sectional study was conducted in 33 benzene‐exposed male workers and 33 unexposed workers from Chinese factories. Air benzene concentrations in the exposed workers ranged from below the detection limit to 24 ppm (median, 2.9 ppm) and were undetectable in the unexposed subjects. Aneuploidies of chromosomes 21, X, and Y in blood lymphocytes were examined by multicolor fluorescence in situ hybridization and were compared to the previously reported aneuploidies in sperm. The results showed that benzene exposure was positively associated with the gain of chromosome 21 but not sex chromosomes in blood lymphocytes. This was in contrast to analysis of sperm, where the gain of sex chromosomes, but not chromosome 21, was significantly increased in the exposed workers. Furthermore, a significant correlation in the gain of sex chromosomes between blood lymphocytes and sperm was observed among the unexposed subjects, but not among the exposed workers. The findings suggest that benzene exposure induces aneuploidies in both blood cells and sperm within the same individuals, but selectively affects chromosome 21 in blood lymphocytes and the sex chromosomes in sperm. Environ. Mol. Mutagen. 2012. © 2011 Wiley Periodicals, Inc.     

48,XXYY综合征合并糖尿病1例的X染色体来源和失活偏移分析

目的 初步探讨48,XXYY综合征合并糖尿病患者的临床特点,并分析该疾病的X染色体来源和失活偏移.方法收集患者的临床资料,抽提患者及其父母的外周血基因组DNA,应用PCR结合HpaⅡ限制性内切酶消化法分析X染色体来源和失活偏移.结果 患者临床表现及实验室检查完全符合48,XXYY综合征,使用二甲双胍和睾酮治疗后患者血糖控制平稳.患者X染色体分别来源于父亲和母亲,两条X染色体均为部分失活,偏移度为0.52.结论 48,XXYY综合征合并糖尿病的发病机制可能与睾酮水平低下、胰岛素抵抗有关.48,XXYY综合征多余X染色体来源于父亲,X染色体不一定存在失活偏移.     

Presence of Y chromosome sequences and their effect on the phenotype of six patients with Y chromosome anomalies

The extent of Y chromosome material was determined in 6 southern African subjects with sex chromosome anomalies. Four of the subjects were phenotypically female, and 2 were phenotypically male. Molecular and cytogenetic findings were correlated with phenotypic expression. An X;Y translocation was found in both male subjects, and in one female subject. The remaining female subjects were characterized by an isodicentric Y, an isochromosome Yq, and a micromarker of undetermined origin, respectively. The individuals were tested for the presence of a number of Y-specific DNA sequences. Molecular findings were generally compatible with the cytogenetic findings, and also with the phenotypic sex of the patients. All the female subjects had Y material and all but one were negative for the sex determining region of the Y (SRY). The somatic Ullrich-Turner-like findings present in 3 of the females were attributed to either the presence of a 45,X cell line and/or a single copy of Xp. The males both showed X;Y translocations without any detectable loss of Y DNA. Although molecularly very similar, the disparate clinical findings in these 2 subjects could have been accounted for by different X inactivation patterns. © 1995 Wiley-Liss, Inc.     

Location of the handedness gene on the X and Y chromosomes

Accumulated data from five handedness surveys show that concordance for sex is slightly but reliably higher among siblings of the same handedness than among those of opposite handedness. This is consistent with Crow's theory that the genetic locus for handedness is in an X-Y homologous region of the sex chromosomes. The small size of the effect is predicted from genetic models in which there is a substantial random component underlying phenotypic left handedness. The findings are relevant to the putative role of cerebral asymmetry in the aetiology of psychosis. © 1996 Wiley-Liss, Inc.     

Buccal cell FISH and blood PCR-Y detect high rates of X chromosomal mosaicism and Y chromosomal derivatives in patients with Turner syndrome

Turner syndrome (TS) is the result of (partial) X chromosome monosomy. In general, the diagnosis is based on karyotyping of 30 blood lymphocytes. This technique, however, does not rule out tissue mosaicism or low grade mosaicism in the blood. Because of the associated risk of gonadoblastoma, mosaicism is especially important in case this involves a Y chromosome. We investigated different approaches to improve the detection of mosaicisms in 162 adult women with TS (mean age 29.9 ± 10.3). Standard karyotyping identified 75 patients (46.3%) with a non-mosaic monosomy 45,X. Of these 75 patients, 63 underwent additional investigations including FISH on buccal cells with X- and Y-specific probes and PCR-Y on blood. FISH analysis of buccal cells revealed a mosaicism in 19 of the 63 patients (30.2%). In five patients the additional cell lines contained a (derivative) Y chromosome. With sensitive real-time PCR we confirmed the presence of this Y chromosome in blood in three of the five cases. Although Y chromosome material was established in ovarian tissue in two patients, no gonadoblastoma was found. Our results confirm the notion that TS patients with 45,X on conventional karyotyping often have tissue specific mosaicisms, some of which include a Y chromosome. Although further investigations are needed to estimate the risk of gonadoblastoma in patients with Y chromosome material in buccal cells, we conclude that FISH or real-time PCR on buccal cells should be considered in TS patients with 45,X on standard karyotyping.