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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.

The excess of 47,XXX and 47,XXY karyotypes found in cytogenetic screening studies of individuals with schizophrenia has given support for an increased risk of psychiatric illness among men and women with sex chromosomal aneuploidy (SCA). Mesial temporal lobe structures, including the amygdala and hippocampus, are thought to be associated with abnormalities of mood and behavior in humans and in the neurobiology of schizophrenia. This study focuses on variations in volumes of mesial temporal lobe structures in men and women with SCA. Utilizing an unselected birth cohort of subjects with SCA and high-resolution magnetic resonance imaging (MRI), we investigated the neuroanatomical consequences of a supernumerary X chromosome on the morphology of the amygdala and hippocampus. Regional and total brain volumes were measured in 10 subjects with 47,XXY, 10 subjects with 47,XXX, and 20 euploid controls. Amygdala volumes were significantly reduced in men with 47,XXY, compared to control men, while the decrease in women with 47,XXX was not as pronounced. Hippocampus volumes were preserved in both groups, compared to same-gender controls. Longitudinal studies of SCA individuals have shown an increased incidence of mild psychopathology and behavioral dysfunction in men with 47,XXY and more overt psychiatric illness in women with 47,XXX, compared to control populations. The alteration in amygdala volumes in individuals with a supernumerary X chromosome may provide a neuroanatomic basis for these findings.

Very little is known about the adult adaptation of individuals with sex chromosome abnormalities (SCA) except for a few reports based upon biased samples of clinically identified patients. This first report from the Denver SCA study on the adult psychosocial adaptation of 36 unselected propositi, identified at birth, shows a continuation of mild psychological and social problems. Psychiatric interviews and self-reported information revealed that adaptation is quite variable, with many of the nonmosaic propositi not faring as well as their siblings, but in a few instances exceeding the success of brothers and sisters. Within this group of SCA subjects a subset demonstrated more marked pathology and a tendency to overrate their social adaptation relative to the psychiatric interviewer, suggesting that the exclusive use of self-report questionnaires may not provide accurate assessment of psychological characteristics in this and other special populations. The full adult SCA behavioral phenotype has not yet been established but is emerging through additional reports from this and other studies of unselected SCA adults. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:200–206, 1999. © 1999 Wiley-Liss, Inc.

We report on a 15-year-old compound heterozygous young woman with fragile X syndrome who has a full mutation of 363 repeats on one X chromosome and a premutation of 103 repeats on the other X chromosome. As predicted, subsequent testing demonstrated that her father carries a premutation (98 repeats) as does her mother (146 repeats). There is only one previous report of a compound heterozygous female with fragile X syndrome. By quantitation of Southern blot signals, the activation ratio for the premutation (the proportion of the premutation on the active X chromosome) was determined to be 0.78. Immunocytochemistry of blood smears showed fragile X mental retardation-1 protein (FMRP) expression in 63.5% of lymphocytes. Cognitively, this woman is functioning in the midrange of involvement for fragile X females. She attends regular classes and receives supplemental assistance for her learning disabilities. She experiences behavior characteristics typical of females with fragile X syndrome including severe shyness, anxiety, panic episodes, mood swings, and attention deficits. She has responded very well to appropriate treatment including fluoxetine for anxiety, methylphenidate for attentional problems, and educational therapy. Am. J. Med. Genet. 83:318–321, 1999. © 1999 Wiley-Liss, Inc.

Objective To investigate the adolescent and early adult adaptation of a group of 47,XXX women as compared with their siblings, addressing developmental differences in adaptation and psychiatric status. Method Subjects included eleven 47,XXX women and nine female sibling controls. Interviews during adolescence and during early adulthood were semi-structured and included a psychiatric evaluation. Four areas of inquiry were (1) relationships with other family members, (2) sense of self-esteem, (3) sexual identity and preference, and (4) responses to life stressors. A DSM-IV psychiatric diagnosis was assigned where appropriate. The Schedule for Affective Disorders and Schizophrenia-Lifetime version was also administered, and assessments of overall functioning and adaptation were completed. Results The 47,XXX women during adolescence and young adulthood were less well adapted; had more stress; had more work, leisure, and relationship problems; had a lower IQ; and showed more psychopathology when contrasted with the comparison group. However, most of the 47,XXX women were self-sufficient and functioning reasonably well, albeit less well than their siblings. Conclusions This longitudinal study has clarified that previously reported outcomes of severe psychopathology and antisocial behavior in individuals with sex chromosome anomalies are rare and variability in the behavioral pheno-type is much larger than originally appreciated. J. Am. Acad. Child Adolesc. Psychiatry, 1998, 37(3):286–291.

Objective: To provide current information on sex chromosome aneuploidies to obstetricians who encounter such diagnoses and who counsel prospective parents faced with the prenatal diagnosis of a sex chromosome aneuploidy. Data Sources: Unbiased information about the natural course of sex chromosome aneuploidy has become available only in the last few years. Current knowledge is based on seven prospective studies on unselected individuals with sex chromosome aneuploidy identified 20–30 years ago. All literature on sex chromosome aneuploidy was reviewed. Karyotypes specifically addressed included the following: 47,XXY, 47,XXX, 47,XYY, 45,X, 45,X/46,XX, 46,XX/47,XXX, and 46,XY/47,XXY. Methods of Study Selection: The international studies followed the affected subjects from birth to young adulthood. All published reports, case studies, and articles were reviewed. Tabulation, Integration, and Results: All prospective studies were included in the course of determining necessary information for obstetricians and prospective parents. Points addressed for each of the aneuploid karyotypes included expected phenotype, reproductive competence, developmental risks, and intervention therapies. Conclusion: Information about sex chromosome aneuploidy can assist obstetricians in providing accurate and comprehensive genetic counseling to parents of affected fetuses, and thereby facilitate the process of making an informed decision about pregnancy management.

Objectives. Children with sex chromosome abnormalities (SCA) are known to be at increased risk for neuromotor, language, learning, and behavioral problems, but little is known of psychosocial adaptation of SCA adolescents. This study was conducted to evaluate psychologic characteristics of unselected SCA adolescents, including socialization, educational progress, seperation from family, and incidence and severity of psychiatric disturbance. Methods. Thirty-nine propositi identified through the screening of 40 000 consecutive Denver newborns, including boys with 47,XXY karyotypes and girls with 47,XXX, 45,X, and partial X monosomy, or SCA mosaic karyotypes, have been followed longitudinally into adolescence. Twenty-seven siblings served as controls. Between 12 and 19 years of age, all participated in blind psychiatric interviews and were administered standardized intelligence and achievement tests. Results. SCA propositi demonstrated a mean IQ score 21 points lower than that of control subjects. In addition, lower mean scores were seen on achievement test results as well as lower overall psychosocial adaptation scores and increased incidence of psychiatric disturbance. Depression was the most frequent psychiatric diagnosis. Propositi were more likely to receive special education assistance in high school and were less likely to graduate from high school than were controls. Of the three nonmosaic propositi groups, the 47,XXX girls demonstrated the poorest overall psychosocial adaptation and highest degree of psychiatric disturbance. Mosaic girls were indistinguishable from control subjects. Marked variability was found among all three nonmosaic groups, with some individuals in each group demonstrating relatively strong psychosocial adaptation. Conclusions. The presence of nonmosaic sex chromosome abnormality increases the risk for impeded cognitive skills, learning abilities, and psychosocial adaptation in adolescence. The factors that allow for stronger adaptation in some of these adolescents include the presence of a stable and supportive family environment. The outlook for adaptation in unselected SCA adults remains uncertain.

Sex chromosome abnormalities (SCAs) are the most frequently occurring chromosomal abnormalities encountered at both prenatal diagnosis and at birth. Approximately 1/400 newborns has an SCA, and incidence at prenatal diagnosis is even greater, 1/250 to 1/300. Physicians and health providers from various specialties are encountering diagnoses of SCAs with increased frequency as more individuals are becoming identified, both prenatally and postnatally. Because these conditions generally have relatively few serious physical implications and because they are extremely variable, genetic counseling is often more complex and challenging than that occurring with an autosomal abnormality. It is imperative that health professionals have the knowledge of content and methodology to provide appropriate counseling to such individuals and their families. During the period from 1964 to 1975, seven international groups (including the Denver group) screened a total of 199,898 consecutive births and identified 307 individuals with SCA. The Denver group has followed more than 40 such individuals from birth to adulthood. In addition, the Denver group has experience in counseling over 1,000 families with a prenatal diagnosis of SCA. Based on these studies and contacts, guidelines for the counseling of individuals and families with SCA are provided. Accurate information must be presented and the variability and imprecise prognosis recognized. Successful counseling strategies include interfamily contact, viewing photographs, and utilizing support groups. Issues of disclosure, follow-up, and anticipatory guidance should be addressed.

This report presents data defining the neuropsychological and cognitive phenotypes of a group of adults with sex chromosome abnormalities identified at birth through the chromosome screening of 40,000 consecutive newborns between 1964 and 1974. In all three nonmosaic groups, reading skills were impaired and intelligence quotients were on average reduced more than 20 points relative to controls. The 47,XXX women demonstrated greatest overall impairment, including reduced scores on tests of conceptualization and problem solving. 45,X women demonstrated impairment in spatial thinking skills, and 47,XXY men in verbal processing skills. No reduced scores were found in the female mosaic group. Marked variability in scores was seen in all groups; some propositi have been unable to hold any job, whereas others have completed college and are professionally employed.

Purpose: This report from the last phase of the 36-year Denver Study provides information about the adult life adaptation of 35 men and women with sex chromosome abnormalities (SCA) followed since their identification at birth. Methods: Sex chromatin screening of 40,000 consecutive newborns between 1964 and 1974 resulted in the cohort of 35 SCA men and women followed to date since birth. Sixteen chromosomally normal siblings served as controls. Data constituting this report was obtained from formal and informal interviews and psychological testing conducted in the final year of this study. Results: The nonmosaic SCA propositi had lower mean intelligence quotients and psychosocial adjustment scores than did siblings. Consistent with these results, propositi also had lower levels of educational achievement and career success, although most have completed school, married, hold full-time employment, and are financially independent. Conclusions: While the SCA adults demonstrated lower levels of cognitive and psychosocial competence, their overall adaptation has been positive, particularly given an early literature suggesting a high rate of psychopathology and severe dysfunction.

Sixty-seven adolescents participated in this protocol, including 42 with sex chromosome abnormalities and 25 controls. Results from a battery of neuropsychological tests indicated karyotype specific patterns of neuropsychological impairment: (1) 47,XXY boys had unimpaired intelligence but reduced abilities in verbal fluency and reading; (2) 47,XXX girls experienced reduced general intelligence accompanied by impaired scores on individual tests of attention, concept formation, spatial thinking, verbal fluency, and academic skills, while retention of memorized information was a relative strength; (3) among the 45,X girls average intelligence level was also reduced along with scores on tests of attention, concept formation, verbal fluency, spatial thinking, and academic skills, and an atypical pattern of hand dominance was identified; (4) test scores in the group of mosaic females did not differ from those of controls. Test scores and patterns of personal adaptation were quite variable in all groups; while eight nonmosaic propositi required intensive special education assistance in their public schooling, eight others have attended college.

Sex chromosome aneuploidy (SCA) occurs in about 1/250 amniocenteses, and the significance of the long-term prognosis of fetuses with SCA is of concern to prospective parents and health care providers. Longitudinal studies in an unselected group of newborn infants with SCA diagnosed postnatally have refuted allegations of mental retardation but have documented an increased risk for developmental problems. Of the 530 phone consultations with parents faced with a prenatal diagnosis of SCA, 68% continued the pregnancy. Twenty of the oldest subsequently born children (now 7–14 years old) were available for follow-up. In this small sample and age group, the propositi are progressing developmentally at a rate comparable to their sibs and are doing better at school and in peer relations than the SCA group diagnosed postnatally. Only 2 have documented IQs as low as 90. The documented IQs of the remainder, none of whom are sex chromosome mosaics, are all over 110. The parent population in this prenatally diagnosed group is unique and different from that of the postnatally diagnosed group in that over 85% of them are college graduates, often professionals, and upper socioeconomic individuals. The developmental competence of this SCA sample may be attributable to the supportive environment provided by these families, all of whom made a conscious decision to continue the pregnancy. © Wiley-Liss, Inc.

Forty-six unselected children with various sex chromosome abnormalities (14 boys with 47, XXY, 4 boys with 47, XYY, 11 girls with 47, XXX, 9 girls with 45, X, and 8 girls with SCA mosaicism), identified through the consecutive chromosome screening of 40,000 Denver newborns, have been followed developmentally and evaluated in a protocol that included intellectual, language, and achievement testing. Controls consisted of 12 chromosomally normal males and 13 chromosomally normal females who were siblings of various propositi. While most SCA children were not mentally retarded, most of the nonmosaic propositi (31/37) received special education help for learning problems. In general, nonmosaic males were less severely affected than nonmosaic females, who demonstrated significantly reduced mean IQ scores on both Wechsler IQ tests. The inference that learning disorders were genetically mediated in this group was further supported by karyotype-specific findings. 47, XXY boys tended to demonstrate lower verbal skills and a specific reading disability. 47, XXX girls, while more globally impaired, demonstrated evidence of a specific weakness in language skills. 45, X girls tended to be globally impaired, but demonstrated a contrasting specific deficit in spatial thinking skills. Mosaic girls were not significantly different than controls on any measure, an outcome likely occurring because of the low percentage of aneuploid cells in these propositae. Variability was present in each group, and no single profile can characterize all children with any specific SCA. The presence of SCA, therefore, must be viewed as a risk factor creating a tendency towards LD but interacting with a host of other genetic and environmental forces to create a range of phenotypic outcomes.

Neuromuscular deficits described in early childhood as motor awkwardness or slow movements are still clinically present in school-aged boys with XXY and XYY sex chromosome aneuploidy. A control group of 14 boys (6 to 19 years of age) and 14 XXY and four XYY boys (6 to 15 years of age), identified by newborn screening, were blindly evaluated by a physical therapist. The Bruininks-Oseretsky Test of Motor Proficiency (BOTMP) was administered and a clinical rating of neurologic status and sensory-motor integration was assigned. On the motor proficiency test, the XXY boys had significantly lower mean scores for upper limb coordination, speed and dexterity, and on gross motor and battery composites. The neuromuscular status of the aneuploid boys was deficient, with hypotonia, apraxia, primitive reflex retention, and problems with bilateral coordination and visual-perceptual-motor integration. This mild to moderate dysfunctional sensory-motor integration, as well as previously described auditory-processing deficits and dyslexia, contributed to school performance below that expected from their cognitive potential.

Forty-six children with sex chromosome abnormalities (SCA), identified in the chromosome screening of 40,000 consecutive newborns between 1964 and 1974, have been studied longitudinally. Language, motor, psychosocial, and school impairment occurred more frequently in the 38 nonmosaic propositi but not in the 8 mosaic propositi, relative to the group of 32 control siblings. Incidences of motor, school, and psychosocial impairment increased dramatically when the SCA children came from dysfunctional families, as rated by the Family Dysfunction Index, but not in control subjects. Biological factors that influence environmental risk are discussed, and the importance of understanding “protective factors” in unaffected SCA children noted.

Eleven unselected 47, XXX girls, now 15 to 22 years of age, have been observed from birth in a prospective study of children with sex chromosome anomalies. A description of their growth and development is presented. The 47, XXX infants were not generally distinguishable from chromosomally normal children in the first year of life, even though there was a slight delay in neuromotor development. By 2 years of age, developmental delays in speech and language often became evident, and speech therapy was often necessitated in the preschool years. Early school problems included speech and language deficiencies, lack of coordination, poor academic performance, and immature behavior; these persisted throughout the school years. By high school age, a 47, XXX girl was generally tall and often subject to somatic complaints. Sexual development was generally normal. Seven of the 11 propositae had a diagnosed psychiatric disorder or disturbance at some time during adolescence. Variability within this syndrome is great; one proposita is in college and another is mentally retarded. The frequency of the diagnosis of the 47, XXX karyotype by genetic amniocentesis is estimated to be 1/1000, the same incidence as in the newborn population. Expectant parents must be counseled as to the significance of this karyotype and prognostic information must be given. Suggested guidelines are included.

Neuromuscular deficits have been described in 47,XXY and 47,XYY boys, but gross and fine motor development of girls with sex chromosome aneuploidy has not been extensively studied. Twenty-one propositae, 8 to 19 years of age, identified through newborn screening to be 45,X, 47,XXX, or 45,X mosaic, and 11 control girls were evaluated by a physical therapist unaware of their genetic constitution. The Bruininks-Oseretsky Test of Motor Proficiency (BOTMP) was administered, and the quality of neuromuscular function was determined. The 45,X and 47,XXX propositae exhibited both gross and fine motor dysfunction, with 12 of 15 BOTMP composite scores below the 10th percentile. The clinical assessment confirmed the BOTMP findings, with 13 propositae exhibiting dysfunctional sensory-motor integration. A delay in the age of independent walking confirmed the consistency of motor developmental dysfunction throughout time. Sex chromosome mosaics were more similar to control girls. The gross and fine motor delays were frequently associated with a moderate to severe language dysfunction which adversely affected classroom performance. Regular developmental assessments of children with sex chromosome aneuploidy, including sensory-motor integration, should assist in the identification of early developmental delays and permit appropriate intervention.

Spatial and linguistic processing efficiency was evaluated in sixty 8- to 18-yr-old children, including thirteen 47,XXY boys, eleven 47,XXX girls, six girls with 45,X, two girls with 46,X,Xq-, and 28 chromosomally normal controls. Results indicated that the 47,XXX girls performed significantly below controls on all four cognitive tests. Scores of the X monosomy group were reduced on both spatial tests, one requiring rapid information processing and one without time requirements, which is consistent with previous reports of spatial thinking deficits in these propositae. The X monosomy girls also had difficulty completing the high efficiency but not the low efficiency verbal tests. Scores in the 47,XXY group did not differ from controls on either spatial test or on the low efficiency verbal task. When required to rapidly access verbal information from memory, however, the performance of these boys was significantly impaired. This finding confirms earlier reports of impeded verbal fluency in these propositi. Alteration in capacity to rapidly process information appears to distinguish 47,XXY boys and X monosomy girls from their chromosomally normal peers, and suggests that adaptations in their educational setting should be introduced to allow additional time to learn and complete work.

This is a report of 327 phone calls to our center concerning the intrauterine diagnosis of sex chromosome abnormalities (SCA). The first author (A.R.) responded to each by counseling either the parents or the referring professional. Sixty-two percent continued the pregnancy. When the parents were counseled directly, the percentage continuing the pregnancy was significantly higher than when the information was transmitted through the professionals. Our results are different from most reports in these situations, and suggest that well-informed couples, counseled by geneticists, are more likely to continue these pregnancies. The possible occurrence of SCA should be considered in preamniocentesis counseling.

Eleven unselected 47,XXX girls, now 15 to 22 years of age, have been observed from birth in a prospective study of children with sex chromosome anomalies. A description of their growth and development is presented. The 47,XXX infants were not generally distinguishable from chromosomally normal children in the first year of life, even though there was a slight delay in neuromotor development. By 2 years of age, developmental delays in speech and language often became evident, and speech therapy was often necessitated in the preschool years. Early school problems included speech and language deficiencies, lack of coordination, poor academic performance, and immature behavior; these persisted throughout the school years. By high school age, a 47,XXX girl was generally tall and often subject to somatic complaints. Sexual development was generally normal. Seven of the 11 propositae had a diagnosed psychiatric disorder or disturbance at some time during adolescence. Variability within this syndrome is great; one proposita is in college and another is mentally retarded. The frequency of the diagnosis of the 47,XXX karyotype by genetic amniocentesis is estimated to be 1/1000, the same incidence as in the newborn population. Expectant parents must be counseled as to the significance of this karyotype and prognostic information must be given. Suggested guidelines are included.