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R J Hagerman

Publications and source records attributed to R J Hagerman.

At least 55 records · Page 3Linked to original sources

A controlled study of longitudinal IQ changes in females and males with fragile X syndrome.

The aim is this study is to compare the longitudinal changes in IQ scores of females and males with fragile X syndrome and controls and to assess the impact on IQ of molecular variations of the FMR-1 gene in males. Medical records from the child development unit at a university-affiliated children's hospital were retrospectively reviewed. Chart review yielded 35 males with fragile X (19 with a fully methylated full mutation, 9 with a mosaic pattern, and 7 with a partially unmethylated full mutation) 16 females with fragile X and a full mutation, 9 female controls, and 9 male controls who had repeated standardized IQ testing separated by 7 months to 13 years. The differences between the first and last IQ scores from the same IQ test were compared by t tests and subsequently by analysis of variance. Overall, a significant IQ decline was seen in 10/35 (28%) of fragile X males, 0/9 (0%) of control males, 6/16 (36%) of fragile X females, and 1/9 (11%) of control females. The initial t tests and analysis of variance showed a significant difference in IQ (p = 0.02) between fragile X males and control males but did not show a significant difference between males and females with fragile X syndrome or between fragile X and control females. When an analysis of covariance was carried out with the initial IQ as a covariable, a significant difference persisted between fragile X and control males, with a greater IQ decline in fragile X males. There were limitations in using the same IQ test. A comparison among the molecular subgroups of males yielded a significant IQ decline in 3/9 (33%) of mosaic males, 6/19 (32%) of fully methylated full mutation males, and 1/7 (14%) of partially methylated full mutation males. An analysis of covariance using the initial IQ and the intertest interval as covariables demonstrated significant differences between the fragile X molecular subgroups and the controls. Our findings show that a substantial percentage of both male and female fragile X patients and female control patients demonstrated significant IQ decline. There was a significant difference in the IQ change between fragile X and control males. There were no significant differences between fragile X and female controls. There were also significant differences in IQ decline among males with different molecular patterns compared with controls. Males with a mosaic pattern versus control males had the most significant decline of the molecular subtypes. Although the numbers were limited, there was no significant IQ decline in males with less than 50% methylation of the full mutation. This suggests that a small amount of FMR-1 protein production, which is often seen in males with less than 50% methylation, protects against significant IQ decline.

Adolescent↗

Expanding the role of the genetic counselor.

The basic components of genetic counseling are informational and educational. The patient's cognitive and emotional presentation and the needs and concerns of the patient are seldom addressed. Females who carry the FMR1 pre and full gene mutation may present with learning, cognitive, and/or emotional difficulties and family members of those diagnosed with fragile X syndrome have ongoing needs and concerns. As a results, genetic counseling for fragile X syndrome offers a unique opportunity within which to expand the role of the genetic counselor. Q-methodology, by using the q-sort, is centered on the family to reproduce the needs and concerns that are consistent with the patient's own experience. Used for sociological research, the q-methodology with specially constructed q-sort items is easily adapted to the genetic counseling setting and can be used for directly assessing the patient's needs and concerns. For our pilot study, 16 items were physically sorted and ranked interdependently by the patient (subject). Thirty-seven patients (29 females and 8 males) participated in our pilot study. Preliminary results show that the age of the proband, length of time of the diagnosis, and parental sex at the time the q-sort is administered impacts the ranking of items thus differentiating needs and concerns. Results have shown that specific items are missing from the lives of subjects. From the information obtained from the q-sort, the genetic counselor can identify needs and concerns of the patient and combine this information with the clinical presentation to work with the patient in a more effective manner.

Adult↗

Molecular-clinical correlations in males with an expanded FMR1 mutation.

Fragile X syndrome is caused by an expansion of a CGG repeat in the FMR1 gene. The CGG repeat number of the FMR1 mutation and the percentage of cells with methylation of the gene were studied in 218 male patients. Physical and cognitive measurements were also performed. Patients were divided into three groups; those with full mutation and complete methylation (n = 160), those with full mutation and partial methylation (n = 12), and those with a mosaic pattern (n = 46). Statistical comparisons were made between males with the fully methylated full mutation and those with a mosaic pattern. Males having full mutation with complete methylation had the lowest IQ scores and greatest physical involvement. These significant differences were seen only in ages after puberty. CGG repeat length did not correlate with IQ or the physical index score in any group. These findings suggest that a partial production of FMR1 protein may predict milder clinical involvement in some males with fragile X syndrome.

Adolescent↗

Adult fragile X syndrome: neuropsychology, brain anatomy, and metabolism.

To understand the implications of suboptimal gene expression in fragile X syndrome -fra(X)-, we sought to define the central nervous abnormalities in fra(X) syndrome to determine if abnormalities in specific brain regions or networks might explain the cognitive and behavioral abnormalities in this syndrome. Cranial and ventricular volumes were measured with quantitative computed tomography (CT), regional cerebral metabolic rates for glucose (rCMRglc) were measured with [18-F]-2-fluoro-2-deoxy-D-glucose (18FDG), and patterns of cognition were determined with neuropsychological testing in ten healthy, male patients with karyotypically proven fra(X) syndrome (age range 20-30 yr). Controls for the CT studies were 20 healthy males (age range 21-37 yr), controls for the PET studies were 9 healthy males (age range 22-31 yr), and controls for the neuropsychological tests were 10 young adult, male Down syndrome (DS) subjects (age range 22-31 yr). The mean mental age of the fra(X) syndrome group was 5.3 yr (range 3.5-7.5 yr; Stanford-Binet Intelligence Scale). Despite comparable levels of mental retardation, the fra(X) subjects showed poorer attention/short term memory in comparison to the DS group. Further, the fra(X) subjects showed a relative strength in verbal compared to visuospatial attention/short term memory. As measured with quantitative CT, 8 fra(X) subjects had a significant (P < 0.05) 12% greater intracranial volume (1,410 +/- 86 cm3) as compared to controls (1,254 +/- 122 cm3). Volumes of the right and left lateral ventricles and the third ventricle did not differ between groups. Seven of eight patients had greater right lateral ventricle volumes than left, as opposed to 9 out of 20 controls (P < 0.05). Global gray matter CMR-glc in nine fra(X) patients was 9.79 +/- 1.28 mg/100 g/minute and did not differ from 8.84 +/- 1.31 mg/100 g/minute in the controls. R/L asymmetry in metabolism of the superior parietal lobe was significantly higher in the patients than controls. A preliminary principal component analysis of metabolic data showed that the fra(X) subjects tended to form a separate subgroup that is characterized by relative elevation of normalized metabolism in the lenticular nucleus, thalamus, and premotor regions. Further, a discriminant function, that reflected rCMRglc interactions of the right lenticular and left premotor regions, distinguished the fra(X) subjects from controls. These regions are part of a major group of functionally and anatomically related brain regions and appear disturbed as well in autism with which fra(X) has distinct behavioral similarities. These results show a cognitive profile in fra(X) syndrome that is distinct from that of Down syndrome, that the larger brains in fragile X syndrome are not accompanied by generalized cerebral cortical atrophy or hypoplasia, and that distinctive alterations in resting regional glucose metabolism, measured with 18 FDG and PET, occur in fra(X) syndrome.

Adult↗

High functioning fragile X males: demonstration of an unmethylated fully expanded FMR-1 mutation associated with protein expression.

Fragile X (fra(X)) males with a standardized IQ score of 70 or higher represent a high functioning (HF) or nonretarded fra(X) male group. This group, which does not include nonpenetrant males, has received little research attention to date. Of 221 fra(X) males who had been evaluated through The Children's Hospital in Denver since 1981 and had completed cognitive or developmental testing, 29 (13%) were high functioning by the above definition. We found that HF males on the whole had a lower cytogenetic score and were younger than retarded fra(X) males, but there was no difference between these two groups in the number of typical fra(X) physical manifestations present. FMR-1 DNA testing was performed on 134 fra(X) males and methylation status was determined for 51 of these. A greater percentage of HF males had a mosaic pattern or an incompletely methylated full mutation than did retarded males. A unique DNA pattern, an unmethylated fully expanded mutation, was discovered in 3 of the highest functioning fra(X) males. Protein studies performed on 2 of these males demonstrated the presence of FMR-1 protein, albeit at lower levels than normal. FMR-1 protein was not present in retarded fra(X) males. Significant FMR-1 protein expression may be responsible for higher cognitive functioning in the 2 males with unmethylated fully expanded mutations compared to retarded fra(X) males.

Adolescent↗

Emotional and neurocognitive deficits in fragile X.

We have studied the neurocognitive deficit in premutation and full mutation women as compared to control women and to explore the relationship between those deficits and the incidence of emotional problems. Four groups of women were examined: two fragile X (fra(X)) negative control groups, one of which grew up in fra(X) families and one not; and two DNA positive groups, one with a premutation (CGG repeats < 200) and one with an expanded mutation (CGG repeats > 200). All women were assessed using the MMPI-2, the SADS-L, and a battery of neuropsychological tests. Full mutation women had lower scores on composite measures of executive function and nonverbal function. There was no difference between the groups in terms of the lifetime incidence of depressive and anxiety disorders on the SADS-L. Full mutation women displayed Lie scales higher than the other groups on the MMPI-2. Neurocognitive measures were not related to SADS-L diagnoses but were related to the Lie scale on the MMPI-2. Finally, number of CGG repeats was related to the neuropsychological variables and the Lie scale.

Adult↗

Evaluation of school children at high risk for fragile X syndrome utilizing buccal cell FMR-1 testing.

We describe a pilot project utilizing saliva to identify the FMR-1 mutation in high-risk special education students from four public school districts in Colorado. The program included presentations to special education teachers regarding fragile X syndrome, parental consent for testing, completion of a behavior checklist by the teachers, identification of special education students at high risk for fragile X syndrome, subsequent brief examination of face and hands, collection of a saliva sample by either Gatorade swish or brushing of the inside of the cheek, and analysis for the FMR-1 mutation by PCR. Equivocal samples were studied by direct DNA testing using Southern blot analysis, and abnormal results were confirmed by a blood analysis for the FMR-1 mutation. Mutant individuals received genetic counseling and medical and educational assessments to optimize treatment and intervention. This pilot project was met with enthusiasm by the schools. Of the first 439 students evaluated, 68% were male with an average age of 7.75 years; 13% were mentally retarded or autistic. Most students referred for the evaluation were learning disabled (51%) and/or had an Attention Deficit Hyperactivity Disorder (ADHD) (35%). The overall prevalence of the FMR-1 mutation was 5 of 439 or 1.1%. This relatively low yield is probably due to the high number of non-retarded but learning disabled students tested. Of the mentally retarded patients tested, 3.5% were positive for the FMR-1 mutation; however, of the non-retarded or learning disabled patients, only 0.79% were FMR-1 positive.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Molecular predictors of cognitive involvement in female carriers of fragile X syndrome.

OBJECTIVE: Fragile X syndrome is caused by a mutation involving expansion of a CGG trinucleotide repeat segment in the fragile X mental retardation-1 (FMR1) gene on the long arm of the X chromosome. This study was undertaken to determine the relative impact of three molecular characteristics of the FMR1 mutation--number of CGG repeats, methylation status, and X inactivation ratio--on the cognitive involvement of female carriers of fragile X syndrome. DESIGN: Retrospective study with new DNA analysis of known female carriers of fragile X syndrome. SETTING: Molecular studies were conducted in a university-based DNA diagnostic laboratory. Patients were originally ascertained through a regional fragile X clinic in a university-affiliated pediatric hospital. PATIENTS: Forty-eight female carriers of fragile X syndrome were studied, including 22 with a premutation (a small expansion to approximately 50 to 200 CGG repeats), 23 with a full mutation (a full expansion to > 200 CGG repeats), and three with both types of mutations (mosaics). RESULTS: Median IQ score was significantly lower for females with a full mutation than for females with a premutation. No significant relationship was found between IQ score and number of CGG repeats or percentage methylation of the mutant allele within each mutation category. In addition, no significant relationship was found between IQ score and the proportion of normal FMR1 alleles on the active X chromosome in the carrier female group as a whole or in either mutation subgroup. Comparisons of leukocytes and saliva-borne epithelial cells in certain full-mutation carriers revealed striking differences in FMR1 mutation sizes. CONCLUSIONS: Mutation category remains the most important predictor of affectedness in female carriers of fragile X syndrome. Our data do not support use of the proportion of normal FMR1 alleles on the active X chromosome as a predictor of cognitive involvement in female carriers with full mutations. Individual tissue-specific differences exist in the heterogeneous sizes of full mutations and in the presence of premutation/full-mutation mosaicism.

Adolescent↗

Social cognition skills among females with fragile X.

Emotion perception and perspective-taking skills were examined among women with or without the fragile X gene. The performance of 56 control women was compared to the performance of 46 women who were carriers of the fragile X gene. Twenty-seven of the carrier women had 0-1% cytogenetic expression and did not appear affected by the gene, whereas the remaining 19 women had > or = 2% cytogenetic expression and did appear affected by the gene. The emotion perception task employed was one for which deficits have been reported among individuals with autism. The results show that performance on this emotion-perception test and the perspective-taking measure was significantly related to full-scale IQ scores, but not to fragile X group status when effects of IQ were removed. Thus the results do not support the hypothesis that perspective-taking or emotion perception deficits are a component of the fragile X phenotype in females and represent an important differentiation between fragile X and autism.

Adolescent↗

Symptoms of schizotypal personality disorder in fragile X women.

OBJECTIVE: The frequency of DSM III-R symptoms of schizotypal personality disorder as it relates to CGG amplification and to the cytogenetic expression of fragile X syndrome was explored. METHOD: Four groups of women were examined: 30 control mothers of children with developmental problems, 17 control women who grew up in fragile X families, 28 women cytogenetically negative but DNA positive for fragile X with a premutation, and 31 women who were DNA positive with an expanded mutation, most of whom were cytogenetically positive. All women were assessed using the Structured Interview for Schizotypy. RESULTS: Eight of the nine women who received the DSM III-R schizotypal personality disorder diagnosis came from the two fragile X groups: four from the premutation group and four from the expanded mutation group. Twenty percent of fragile X carriers who received the gene from their mother, but none who received the gene from their father demonstrated schizotypal personality disorder. CONCLUSIONS: Women who carry the premutation and women with the full mutation may both show schizotypal features, although less commonly than previously reported.

Adolescent↗

Behavioral and psychiatric disorders in adult male carriers of fragile X.

OBJECTIVE: In the present study we examined the incidence of psychiatric and behavioral problems among male carriers of the fragile X gene. METHOD: Retrospective data on carrier males were gathered using the family informant method. Each of 56 fragile X carrier women was interviewed about her father by an examiner blind to the father's carrier status. The interviewer administered measures of (1) behaviors related to DSM-III-R Axis I disorders, (2) adult attention-deficit hyperactivity disorder (ADHD) behaviors, (3) parental bonding skills, and (4) abusive behaviors. The endorsements from 24 women with fragile X fathers were compared with endorsements from 32 women with nonfragile X fathers. RESULTS: The results show a higher incidence of psychopathology among the fragile X males (relative to nonfragile X fathers) for behaviors related to adult ADHD, parental bonding, abuse; and particularly for alcohol abuse/dependence and obsessive-compulsive disorder behaviors. CONCLUSIONS: These findings support the hypotheses that some "nonpenetrant" males may indeed be mildly affected carriers and that there is a broad spectrum of involvement among carrier males.

Adult↗

A study of the physical, behavioral, and medical phenotype, including anthropometric measures, of females with fragile X syndrome.

The physical features of fragile X, including a long face, prominent ears, and hyperextensible joints, are present in affected males and females. Cytogenetically negative heterozygotes have been considered to be unaffected by the fragile X mental retardation-1 (FMR-1) gene. This study investigated the penetrance of the FMR-1 gene in cytogenetically negative but DNA-positive heterozygotes with a premutation (cytosine guanine guanine [CGG] amplification in the 50 to 200 repeat range), compared with carriers with a full mutation (> 200 CGG repeats) and control subjects. One hundred thirty-nine women with normal IQs between the ages of 18 and 45 years were studied. All underwent cytogenetic and DNA testing to determine their fragile X carrier status. A medical history-taking and a physical examination, including selected anthropometric measurements, were performed. Results indicate that the FMR-1 mutation mildly affects the physical phenotype of individuals even in the premutation state, although less dramatically than more affected heterozygotes. Carriers with a premutation differed significantly from control subjects in overall physical index score and in the anthropometric measure of ear prominence. These results suggest a phenotypic impact of the FMR-1 mutation even at the 50 to 200 CGG repeat length.

Adolescent↗

The neurocognitive phenotype of female carriers of fragile X: additional evidence for specificity.

The specificity of the neurocognitive profile among women with the fragile X gene, in relation to cytogenetic expression, was examined among 22 women with > or = 2% expression, 35 0% obligate carriers, and 60 controls. Measures were obtained for intellectual ability; achievement; and verbal, nonverbal, memory, and executive functions. Findings show that no group consistently demonstrated global deficits in the verbal, nonverbal or memory domains. In contrast, even when controlling for the effects of IQ, the expressing women exhibited (1) deficits on measures of executive function, (2) deficits in measures of attention and visual-spatial skills, and (3) enhanced performance on verbal, but not figural, memory. No deficits were seen among obligate carriers. This study supports the notion that executive function deficits and/or visual-spatial skills may account for the behavioral and cognitive manifestations of fragile X.

Adolescent↗

Specific frontal lobe deficits among women with the fragile X gene.

The neurocognitive phenotype of fragile X and its relation to cytogenetic expression were examined among 10 fragile X women with > or = 2% expression, 10 0% obligate carriers, and 10 controls. Measures were obtained for intellectual ability, achievement, and verbal, nonverbal, memory, and frontal lobe functions. Results show that no group demonstrated deficits on verbal, nonverbal, or memory measures. In contrast, when controlling for effects of IQ, the expressing fragile X women exhibited (1) deficits on measures of frontal lobe functioning, and (2) enhanced performance on verbal, but not figural, memory. Frontal lobe deficits may account for behavioral and cognitive manifestations of fragile X.

Adolescent↗

The fragile X syndrome.

We have begun to appreciate that the extent of this disorder is much wider than merely mental retardation. It is also a common cause of learning and emotional problems in mildly affected female carriers with normal IQs. These children present an enormous challenge to all child-care providers, be they in medicine, education, or in various therapy disciplines. Early identification is essential, and the key to effective management is an innovative and multidisciplinary approach. As disciplines become more familiar with and knowledgeable about this frequently occurring form of mental retardation or cause of learning disabilities, they should become more adept at early identification and early referral for support and intervention.

Autistic Disorder↗