Increased Frequency of Clonal Hematopoiesis of Indeterminate Potential in Bloom Syndrome Probands and Carriers

Background

Bloom Syndrome (BSyn) is an autosomal recessive disorder caused by biallelic germline variants in BLM, which functions to maintain genomic stability. BSyn patients have poor growth, immune defects, insulin resistance, and a significantly increased risk of malignancies, most commonly hematologic. The malignancy risk in carriers of pathogenic variants in BLM (BLM variant carriers) remains understudied. Clonal hematopoiesis of indeterminate potential (CHIP) is defined by presence of somatic mutations in leukemia-related genes in blood of individuals without leukemia and is associated with increased risk of leukemia. We hypothesize that somatic mutations driving clonal expansion may be an underlying mechanism leading to increased cancer risk in BSyn patients and BLM variant carriers.

Methods

To determine whether de novo or somatic variation is increased in BSyn patients or carriers, we performed and analyzed exome sequencing on BSyn and control trios.

Results

We discovered that both BSyn patients and carriers had increased numbers of low-frequency, putative somatic variants in CHIP genes compared to controls. Furthermore, BLM variant carriers had increased numbers of somatic variants in DNA methylation genes compared to controls. There was no statistical difference in the numbers of de novo variants in BSyn probands compared to control probands.

Conclusion

Our findings of increased CHIP in BSyn probands and carriers suggest that one or two germline pathogenic variants in BLM could be sufficient to increase the risk of clonal hematopoiesis. These findings warrant further studies in larger cohorts to determine the significance of CHIP as a potential biomarker of aging, cancer, cardiovascular disease, morbidity and mortality.

Public health monitoring of developmental disabilities with a focus on the autism spectrum disorders

Developmental disabilities (DDs) are conditions characterized by physical, cognitive, psychological, sensory, adaptive, and/or communication impairments manifested during development. Approximately 17% of individuals in the United States 18 years and younger have a DD, and for most children the cause of their condition is unknown. Of particular interest are the autism spectrum disorders (ASDs), characterized by unusual social, communication, and behavioral development. Previously autism was thought to be a rare condition, but the number of children receiving services for an ASD has increased dramatically in the last decade. Concerns about increases in DDs, particularly ASDs, their causes, and the high costs of intervention have highlighted the need for systematic public health monitoring. Service provider data, such as annual reporting of special education services or of state DD programs, do not provide a complete estimate of the rates for DDs, including ASDs. Unlike genetic metabolic disorders or congenital hearing loss (HL) for which newborn screening programs can provide accurate prevalence rates, there are currently no genetic or biologic markers for the ASDs to enable consistent and early identification of affected children. Centers for Disease Control and Prevention's (CDC) Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP) is a model for population monitoring of ASDs/DDs that has been implemented in other states. This article discusses the role of ASD/DD tracking in public health, as well as the challenges of ASD/DD tracking, including case definition and identification, associated conditions, linkages, and data access.

Improving access to and utilization of genetic services in Arizona's Hispanic population

This abstract presents a model project aimed to train community lay health workers about genetics, increase cultural competency of genetic services providers, and provide local access to genetic services in primarily Hispanic communities in the state of Arizona. Health Start, a community-based prenatal outreach program, served as the basis for providing genetic education and services. A genetics training curriculum was developed and training of community lay health workers was provided. Cultural and Spanish language training was provided for all genetic services providers. Pediatric genetics outreach clinics were established in eight communities. Community-based lay health workers eagerly incorporate genetic information into their public health knowledge base, but this may not lead to acceptance of these personnel by local health care providers as sources of referrals for specialized health services such as genetics. Cultural competence training of genetic service providers is enthusiastically accepted and utilized in the provision of locally accessible genetics clinics.

Molecular mechanisms in neurologic disorders

Although many pediatric neurologic disorders, such as epilepsy and mental retardation, are the result of a combination of genetic and environmental factors, many others are the result of mutations of single genes. Most of these single gene traits are inherited in autosomal dominant, autosomal recessive, or X-linked fashion. The diversity of mutations that are responsible for these diseases produces variability in phenotypic expression. However, there are other important features of many neurologic disorders that cannot be explained by standard models of mendelian inheritance. This review focuses on recently described mechanisms, such as genomic imprinting, germline mosaicism, mitochondrial inheritance, and triplet repeat expansion. The diagnostic evaluation, prognostic significance, and recurrence risk for specific neurogenetic disorders is correlated with these underlying disease mechanisms.

Variable presentation of Rothmund-Thomson syndrome

The recent finding that a subset of patients with Rothmund-Thomson syndrome (RTS) have mutations of a helicase gene has prompted reexamination of the phenotypes of individuals diagnosed with this disorder. We report on two patients with variable presentations of RTS. Initial presenting symptoms included growth deficiency and absent thumbs in one patient and osteogenic sarcoma and poikiloderma in the second patient. The growth-deficient patient was diagnosed with growth hormone deficiency and had a subnormal response to growth hormone supplementation. Neither malformations nor growth deficiency were present in the patient with osteogenic sarcoma, and her only other manifestation of RTS was poikiloderma. The diagnosis of RTS should be considered in all patients with osteogenic sarcoma, particularly if associated with skin changes.

Blepharophimosis: a causally heterogeneous malformation frequently associated with developmental disabilities

We report on 22 individuals referred for genetic evaluation because of blepharophimosis. Fourteen of these patients had the blepharophimosis syndrome: 5 familial and 9 sporadic. Mental retardation or developmental delay was seen in 8 of the 12 children in whom this could be assessed. Eight of 22 children had a malformation syndrome other than the blepharophimosis syndrome. All 8 of these children were mentally retarded or developmentally delayed. Two of these 8 had recognized disorders (branchio-oto-renal syndrome and a ring 4 chromosome); the remaining 6 had unrecognized malformation syndromes. Based on this information, it is suggested that children with blepharophimosis be evaluated carefully for underlying conditions and that they be observed for developmental disabilities because of the frequent association.

Evaluation of mental retardation: recommendations of a Consensus Conference: American College of Medical Genetics

A Consensus Conference utilizing available literature and expert opinion sponsored by the American College of Medical Genetics in October 1995 evaluated the rational approach to the individual with mental retardation. Although no uniform protocol replaces individual clinician judgement, the consensus recommendations were as follows: 1. The individual with mental retardation, the family, and medical care providers benefit from a focused clinical and laboratory evaluation aimed at establishing causation and in providing counseling, prognosis, recurrence risks, and guidelines for management. 2. Essential elements of the evaluation include a three-generation pedigree: pre-, peri-, and post-natal history, complete physical examination focused on the presence of minor anomalies, neurologic examination, and assessment of the behavioral phenotype. 3. Selective laboratory testing should, in most patients, include a banded karyotype. Fragile X testing should be strongly considered in both males and females with unexplained mental retardation, especially in the presence of a positive family history, a consistent physical and behavioral phenotype and absence of major structural abnormalities. Metabolic testing should be initialed in the presence of suggestive clinical and physical findings. Neuroimaging should be considered in patients without a known diagnosis especially in the presence of neurologic symptoms, cranial contour abnormalities, microcephaly, or macrocephaly. In most situations MRI is the testing modality of choice. 4. Sequential evaluation of the patient, occasionally over several years, is often necessary for diagnosis, allowing for delineation of the physical and behavioral phenotype, a logical approach to ancillary testing and appropriate prognostic and reproductive counseling.

Clinical and biochemical spectrum of patients with RSH/Smith-Lemli-Opitz syndrome and abnormal cholesterol metabolism

RSH/Smith-Lemli-Opitz (RSH/SLO) syndrome is an autosomal recessive malformation syndrome recently shown to be associated with a severe deficiency of cholesterol biosynthesis and markedly elevated plasma and tissue levels of 7-dehydrocholesterol (7-DHC), the immediate precursor of cholesterol in the Kandutsch-Russell biosynthetic pathway. Because these biochemical abnormalities permit a reassessment of RSH/SLO on biochemical criteria rather than less specific physical criteria, we review here the clinical and biochemical characteristics of our first 80 patients with abnormally increased levels of 7-DHC. The study population included 68 index patients and 12 additional relatives identified by quantification of 7-DHC and cholesterol in plasma, amniotic fluid, or cultured fibroblasts, lymphoblasts, or amniocytes. As demonstrated in other clinical syndromes when redefined biochemically, we have found a wider range of clinical expression of RSH/SLO than previously recognized. These newly recognized atypical RSH/SLO patients included several with no malformations other than syndactyly of the toes and, at the other extreme, patients with frank holoprosencephaly or multiple visceral anomalies who died in utero. Syndactyly of toes 2 and 3 was the most common malformation, occurring in all but one of 80 patients. The best biochemical predictor of clinical severity was the plasma cholesterol level, which decreased with increasing clinical severity. However, at least 10% of patients, including one newborn infant, had normal cholesterol levels at the time of diagnosis and would have been missed without specific quantification of 7-DHC. Not unexpectedly, several patients carrying a clinical diagnosis of RSH/SLO were found to have normal levels of all plasma sterols and apparently normal cholesterol biosynthesis in cultured cells. A comparison of the frequency of anomalies in our biochemically identified patients with similar data from previously reported clinical series suggests that up to 25% of reports of RSH/SLO in the literature may describe genetic conditions other than RSH/SLO with 7-DHC-emia.

Cardiovascular malformations in Smith-Lemli-Opitz syndrome

We reviewed 215 patients (59 new, 156 from the literature) with Smith-Lemli-Opitz syndrome (SLOS), and found that 95 (44%) had a cardiovascular malformation (CVM). Classifying CVMs by disordered embryonic mechanisms, there were 5 (5.3%) class 1 (ectomesenchymal tissue migration abnormalities), 56 (58.9%) class II (abnormal intracardiac blood flow), 25 (26.3%) class IV (abnormal extracellular matrix), and 5 (5.3%) class V (abnormal targeted growth). Comparing the frequencies of individual CVMs in this series with a control group (the Baltimore-Washington Infant Study), there were 6 individual CVMs which showed a significant difference from expected values. When frequencies of CVMs in SLOS were analyzed by mechanistic class, classes IV and V were significantly more frequent, and class I significantly less frequent, than the control group. Although CVMs in SLOS display mechanistic heterogeneity, with an overall predominance of class II CVMs, the developmental error appears to favor alteration of the cardiovascular developmental mechanisms underlying atrioventricular canal and anomalous pulmonary venous return. This information should assist the clinical geneticist evaluating a patient with possible SLOS, and should suggest research direction for the mechanisms responsible for the SLOS phenotype.

The effects of peer ridicule on depression and self-image among adolescent females with Turner syndrome

PURPOSE

This study attempted to examine the effects of body image, height dissatisfaction, and peer ridicule on depression and self-image among adolescent females with Turner syndrome.

METHODS

A prospective, cross-sectional survey examined 59 subjects' responses to standardized measures of depression, self-image, body image, height perception, and teasing.

RESULTS

Descriptive statistics found the mean age of subjects to be 14.8 years (range: 13-19). Approximately 30% reported cardiac defects and 17% indicated kidney anomalies. Only five experienced spontaneous menses and 61% indicated they were receiving estrogen replacement therapy. Linear regression analyses examined the effects of body image, height perceptions, and peer ridicule on depression and self-image scores. The first regression analysis found a five-step model to account for 39% of the variance, with peer ridicule of general appearance being the most important variable. The second linear regression (R2 = .3248, P < .0004) also found peer teasing of general appearance to be significantly associated with self-image scores. Discrepancy scores between ideal versus current body shape or height, as well as teasing about these issues, appeared to be unrelated to depression and self-image among our subjects.

CONCLUSION

These data suggest that peer ridicule is a domain that requires ongoing assessment by health care providers, as it appears to be an important contributor to mental health problems. Social skill interventions that emphasize strategies to manage teasing, assertively respond to negative statements, and teach effective coping skills are key variables to minimize the emotional discomfort these young women may experience.

Health care utilization and perceptions of health among adolescents and adults with Turner syndrome

We surveyed women aged 12 years and older who are members of the Turner Syndrome Society of the United States in regard to their health history, current health status, and health care utilization practices to identify the range of health problems and health care practices in this group. The mean age at diagnosis was 10.8 years, and an endocrinologist (41%) or pediatrician (35%) was most likely to make the initial diagnosis. Individuals over age 35 years were diagnosed with Turner syndrome and begun on estrogen replacement therapy at a significantly older age than those who were in younger age groups. Seventy-five percent of the respondents had required some type of surgical procedure, and 14% had been hospitalized within the previous year. Ninety-four percent of women rated their overall health as good to excellent, while 6% rated it fair to poor. In the 12-17-year age group, 89% of the young women were either currently taking or had previously taken growth hormone. The prevalence of major depressive symptoms was slightly higher than the general population for adolescents but similar to the general population for adults. For adult respondents, ratings of fair to poor health were significantly associated with increased outpatient visits. Growth hormone use was significantly associated with increased visits in the adolescent population. Based on these data, it appears that the clinical care of individuals with Turner syndrome has improved, but that they continue to have relatively high hospitalization rates and utilization of subspecialty services. Despite these health problems, most respondents demonstrated good adjustment as determined by standardized mental health measures.

Contribution of heritable disorders to mortality in the pediatric intensive care unit

OBJECTIVES

To determine the percentage of patients dying in the pediatric intensive care unit (PICU) who have heritable disorders and to compare vital statistics classification of underlying cause of death with underlying heritable disorder identified from medical record review.

DESIGN

Retrospective medical record review.

SETTING

The PICU of a university-affiliated hospital.

METHODS

Medical records were reviewed for all deaths occurring in the PICA over a 5-year period. Further review, including hospital course, clinical findings, and the presence or absence of a genetic evaluation, was accomplished for those patients found to have a chromosome abnormality, recognized syndrome, single major malformation, or unrecognized syndrome. Underlying cause of death classification obtained from the Center for Health Statistics, Arkansas Department of Health was reviewed to determine the frequency with which the underlying heritable disorder was recorded.

RESULTS

Fifty-one of 268 (19%) deaths during the study period were in patients with heritable disorders. Of these 51 patients, eight (16%) had chromosome abnormalities, 17 (33%) had a recognized syndrome, 15 (29%) had a single primary defect in development, and 11 (22%) had an unrecognized syndrome. Genetic evaluation was carried out on 45% of patients, with the frequency of evaluation differing between categories of patients with heritable conditions. When underlying cause of death from vital statistics classification was reviewed, 21 of 51 (41%) records did not include the underlying heritable disorder.

CONCLUSIONS

Heritable disorders are a frequent cause of mortality in the PICU. Vital statistics classification of underlying cause of death in this population often fails to identify heritable disorders, leading to an underascertainment of these conditions in mortality statistics. Improved cause of death classification procedures will be necessary to target public health interventions to etiology-specific populations.

Ehlers-Danlos syndrome, type VIII presenting with periodontitis and prolonged bleeding time

We report on a case of Ehlers-Danlos syndrome, probable type VIII (EDS VIII) in a 6-year-old girl with severe periodontitis, extensive bruising of the shins, abnormal bleeding time, and thin body habitus. The structure and biosynthesis of types I and III colagen were normal. Desmopressin (DDAVP) was found to correct the bleeding time, and the patient underwent an uneventful dental procedure after DDAVP therapy. The finding of childhood or juvenile periodontitis should prompt consideration of a diagnosis of EDS, particularly type VIII, and alert the clinician to the possibility of a treatable bleeding abnormality.

Chromosome instability in ICF syndrome: formation of micronuclei from multibranched chromosomes 1 demonstrated by fluorescence in situ hybridization

We report on a new patient with immunodeficiency, centromeric heterochromatin instability, and facial anomalies (the ICF syndrome). Studies with traditional cytogenetic methods demonstrate that aberrations in this syndrome primarily involve the centromeric regions of chromosomes 1 and 16. We applied fluorescence in situ hybridization (FISH) using "painting" probes for chromosomes 1 and 16 to document the progression of centromeric instability from simple decondensation aberrations to the subsequent formation of complex multibranched chromosomes 1, and finally to the interphase aberrations of nuclear projections and micronuclei involving both chromosomes 1 and 16. The loss of the large multibranched chromosome 1 configurations from the cells as micronuclei suggests that the centromeric aberrations subsequently interfere with normal chromosome movement at anaphase in ICF syndrome. Circular areas of counterstained chromatin were observed by FISH in the micronuclei corresponding to the intertwined segments of centromeric heterochromatin seen involving multibranched chromosomes 1 in the patient's G-banded chromosome study. The current hypothesis of recessive inheritance for this disorder suggests that the chromosomal aberrations are not a causative event in this syndrome; however, the chromosome aberrations are clearly an important basic diagnostic criterion.

Clinical and molecular characterization of patients with distal 11q deletions

Jacobsen syndrome is caused by segmental aneusomy for the distal end of the long arm of chromosome 11. Typical features include mild to moderate psychomotor retardation, trigonocephaly, facial dysmorphism, cardiac defects, and thrombocytopenia, though none of these features are invariably present. To define the critical regions responsible for these abnormalities, we studied 17 individuals with de novo terminal deletions of 11q. The patients were characterized in a loss-of-heterozygosity analysis using polymorphic dinucleotide repeats. The breakpoints in the complete two-generation families were localized with an average resolution of 3.9 cM. Eight patients with the largest deletions extending from 11q23.3 to 11qter have breakpoints, between D11S924 and D11S1341. This cytogenetic region accounts for the majority of 11q- patients and may be related to the FRA11B fragile site in 11q23.3. One patient with a small terminal deletion distal to D11S1351 had facial dysmorphism, cardiac defects, and thrombocytopenia, suggesting that the genes responsible for these features may lie distal to D11S1351. Twelve of 15 patients with deletion breakpoints as far distal as D11S1345 had trigonocephaly, while patients with deletions distal to D11S912 did not, suggesting that, if hemizygosity for a single gene is responsible for this dysmorphic feature, the gene may lie distal to D11S1345 and proximal to D11S912.

Deaths associated with renal agenesis: a population-based study of birth prevalence, case ascertainment, and etiologic heterogeneity

We report on deaths associated with renal agenesis among 211,704 consecutive births. Sources included birth and death certificates and an active birth defects surveillance system. Medical review and classification of cases were performed for 1985-1990 events. Sixty-one cases of renal agenesis were identified, and review of records was possible for 59 of the 61 cases. Of these 59 cases, 36 (61%) were confirmed, 5 (8%) were questionable, and 18 (31%) were incorrectly coded. The prevalence of confirmed cases is thus estimated at 17/100,000 births (14.2/100,000 births, excluding elective terminations and fetal deaths). Records incorrectly coded were most often those with multicystic dysplasia. Approximately one-third of cases was found by the birth defects surveillance system alone, confirming the utility of this data source for prevalence estimates. Isolated renal agenesis accounted for 44% of confirmed cases; other diagnoses included VATER association (19%), unrecognized multiple malformation syndromes (17%), exstrophy of the cloaca sequence (14%), and chromosome disorders (6%). Based on these data, prevalence rates for ICD code 753.0 and death include overascertainment of cases from erroneous coding of multicystic dysplasia and underascertainment of cases with unilateral renal agenesis associated with other malformations. Population-based ascertainment of cases by active surveillance methods and rigorous diagnostic coding standards are required to improve the accuracy of these rates. Targeted investigations of distinct subclassifications will be necessary to identify specific etiologic factors.

Contribution of genetic disorders to neonatal mortality in a regional intensive care setting

We examined the contribution of chromosomal abnormalities, mendelian disorders, and birth defects to mortality in a regional neonatal intensive care unit by medical record review of neonatal deaths in that unit. Of a total of 296 infant deaths during the 5-year period June 1986 to May 1991, 69 (23.3%) had a genetic disorder. By diagnostic category, 18.8% had a chromosomal abnormality, 10.1% had a mendelian condition, 42% had a single primary defect in development, and 29% had an unrecognized pattern of malformation. The rate of autopsy and genetic evaluation differed markedly between these diagnostic categories. A comparison was made of underlying cause of death determined from medical records with underlying cause as classified by vital statistics nosologic procedures. No death certificate was on file for two of the deaths; for the remaining 67, 27 (40.3%) had an erroneous or misleading underlying cause of death as determined from vital statistics. The important contribution of genetic disorders to neonatal mortality in this high-risk population and the relative underrecognition of these disorders by vital statistics sources indicate that efforts aimed at reducing neonatal mortality will require a full range of preventive health activities, including preconception, prenatal and perinatal assessment, and counseling. Improved data collection techniques need to be developed to understand the contribution of this group of conditions to total neonatal mortality.

Duplication and deletion of chromosome band 2(p21p22) resulting from a familial interstitial insertion (2;11)(p21;p15)

Routine amniocentesis for advanced maternal age led to the prenatal diagnosis of a fetus with a karyotype of a 46,XX,del(2)(p21p22). At delivery the baby had holoprosencephaly as the major clinical finding, which has been associated with a deletion of band 2p21 in several other case reports. Chromosome studies of the parents showed a normal 46,XY karyotype in the father, and a balanced interstitial insertion 46,XX dir ins (11;2)(p15.1;p21p22) in the mother. Subsequent chromosome studies of other relatives documented a 23-year-old half-brother of the proposita with a partial trisomy for the segment deleted in the proposita. The half-brother showed the derivative chromosome 11 from the mother, resulting in a 46,XY,der(11)dup(2)(p21p22) karyotype. Major clinical findings include short stature, mild developmental delay, and behavior abnormalities. A half-sister of the proposita is also a balanced carrier of the dir ins (11;2) (p15.1;p21p22.2). The association of the deletion chromosome band 2p21 and the clinical finding of holoprosencephaly is further supported by the findings in this family.

Ocular anomalies in the alagille syndrome (arteriohepatic dysplasia)

BACKGROUND

The Alagille syndrome (arteriohepatic dysplasia) is a well-recognized multiple malformation syndrome consisting of a paucity of intrahepatic bile bile ducts, peripheral pulmonary artery hypoplasia with variable cardiac abnormalities, cholestatic facies, butterfly-like vertebral arch defects, and variable ocular anomalies, most commonly posterior embryotoxon and pigmentary retinopathy.

METHODS

The authors studied ocular findings in six patients from two families with Alagille syndrome to characterize more fully the spectrum of ocular anomalies in this disorder.

RESULTS

Ocular anomalies consisted of a peculiar mosaic pattern of iris stromal hypoplasia in all patients, posterior embryotoxon and microcornea in five patients, anomalous optic discs in five patients, regional peripapillary retinal depigmentation in three patients, and a congenital maculopathy in one patient.

CONCLUSION

The Alagille syndrome comprises a broad spectrum of ocular anomalies involving the cornea, iris, retina, and optic disc. In the setting of neonatal cholestasis, the findings of microcornea, posterior embryotoxon, mosaic iris stromal hypoplasia, regional peripapillary depigmentation, congenital macular dystrophy, and anomalous optic discs should suggest the diagnosis of Alagille syndrome.

Congenital diaphragmatic hernia in the Brachmann-de Lange syndrome

We present 12 children with typical Brachmann-de Lange syndrome and congenital diaphragmatic hernia. Affected children were more likely to be of low birth weight and to have major upper limb malformations. Hernia repair was attempted in 4 of these children, and only one survived past 12 months. Newborn infants with congenital diaphragmatic hernia should be examined carefully for evidence of the Brachmann-de Lange syndrome because diagnosis of this condition may influence their clinical management and prognosis.

Radiological features in Brachmann-de Lange syndrome

Brachmann-de Lange syndrome (BDLS) is a well-delineated disorder consisting variably of pre- and postnatal growth deficiency, microbrachycephaly, characteristic face, hypertrichosis, visceral anomalies, and limb defects consisting primarily of variable limb reduction defects, micromelia, and elbow abnormalities. The course is usually marked by initial hypertonicity, low-pitched weak cry, feeding problems, and behavioral problems with marked mental deficiency. In classical cases there is rarely any difficulty in making the diagnosis, but for mildly affected cases, it may be difficult to feel secure about the diagnosis. In an effort to increase the precision of diagnosis for mildly affected cases, we reviewed roentgenograms in 21 cases of Brachmann-de Lange syndrome, as well as previously published descriptions of the radiological manifestations. Unusual radiologic manifestations were related primarily to the limb anomalies, and these were often asymmetric. These manifestations included digital abnormalities, which ranged from acheiria to oligodactyly, hypoplasia of the thumb and first metacarpal, clinodactyly of the fifth finger, or ectrodactyly. Long bone abnormalities included ulnar a/hypoplasia, dysplasia of the radial head, or fusion of the elbow. When there was a single forearm bone, there was often fusion at the elbow and oligodactyly, which made it difficult to determine whether the radius or ulna was absent. Other radiologic manifestations included 13 ribs with precocious sternal fusion, and micrognathia. We suggest that these radiologic manifestations could increase diagnostic precision in mildly affected cases.

Malformations and minor anomalies in non-trisomic, autosomal aneuploidy

We examined the medical records of 43 individuals with non-trisomic, autosomal aneuploidy evaluated by the Arkansas Genetics Program. Birthweight and the presence of malformations and minor anomalies by organ system were analyzed on each patient. Low birthweight was present in 28% (N = 12) of the patients, 72% (N = 31) of the subjects had a malformation, and 93% (N = 40) had a minor anomaly. Of the entire sample, the most common site of a malformation or minor anomaly was the limbs (79%). The most common site of a malformation was the head (21%), eyes (21%), or heart (26%). If a malformation was present, the head was significantly more likely (P < .04) than another body system to be the site of an additional malformation or minor anomaly. A malformation or minor anomaly of the ears was significantly more likely (P < .03) to be present when there was an associated eye anomaly than when no anomaly of the eye was identified. These data have implications for chromosome screening of individuals with malformations or minor anomalies and for the clinical evaluation of those found to have non-trisomic autosomal aneuploidy.

Perinatal lethal conditions: the effect of diagnosis on decision making

OBJECTIVE

To identify factors influencing pregnancy management decisions following identification of a perinatal lethal condition.

METHODS

One hundred thirty pregnancies with perinatal lethal conditions diagnosed before 24 weeks' gestation were examined. Information collected included demographic data, estimated gestational age at presentation, referral indication, nature of the defect, and performance of autopsy.

RESULTS

Eighty-seven families elected to abort affected pregnancies and 43 elected to continue. Demographic factors did not influence decision making, nor did gestational age at diagnosis or referral indication. When comparing the diagnosis of one lethal condition with diagnoses of all other lethal conditions, pregnancies with a central nervous system defect or severe urinary tract defect were more often aborted; those with unexplained severe oligohydramnios and twin pregnancies in which at least one twin was affected were more often continued. Autopsy was obtained much more often in pregnancies that were aborted than in those that were continued.

CONCLUSION

The type of defect correlates well with the pregnancy management decision. It is important to consider the type of malformation, certainty of the diagnosis, and level of medical understanding when counseling patients after the diagnosis of a lethal fetal defect. Because many patients will continue pregnancies diagnosed with a perinatal lethal condition, the physician should convey understanding and acceptance of a decision not to abort such a pregnancy. The importance of follow-up testing, including autopsy when appropriate, should be stated clearly.

Aicardi syndrome: more than meets the eye

An eight-month-old girl with infantile spasms and apparent blindness had electroencephalographic findings compatible with Aicardi syndrome. In addition to optic nerve hypoplasia, there were multiple congenital retinal malformations in the right eye, including chorioretinal lacunae, anomalous retinal vessels, posterior scleral ectasia, and a peripheral fibrous ridge. Magnetic resonance imaging demonstrated agenesis of the corpus callosum, absence of the septum pellucidum, optic nerve and chiasmal hypoplasia, pachygyria, cortical heterotopias, colpocephaly, and hypoplasia of the cerebellar vermis. This patient illustrates the broad spectrum of cerebroretinal malformations now known to characterize Aicardi syndrome.

High-resolution cytogenetic characterization of telomeric associations in ring chromosome 19

High-resolution cytogenetic studies of a normal individual with ring chromosome 19 indicate that, at the late-to-mid prophase level of band resolution, no apparent chromosomal material is missing, and that telomeric fusion/association, not deletion, is the cause of the ring chromosome formation. Sub-band analysis of the telomeric fusion shows thin chromatin filaments between the telomeres of some of the very elongated ring chromosomes, which cannot be resolved by metaphase chromosome analysis. The ring chromosome found in this individual shows evidence of the characteristic instability associated with ring chromosomes, including duplicated segments, double rings, and subsequent loss of the ring resulting in cells with monosomy 19. The lack of phenotypic effect and the unstable ring behavior, unlike previously reported patients with ring 19, support the formation of this ring by telomeric association.

Variable presentation of cytochrome c oxidase deficiency

OBJECTIVE

To describe three patients with cytochrome c oxidase deficiency.

DESIGN

Patient series.

SETTING

Tertiary care children's hospital in Arkansas.

PARTICIPANTS

A sibling pair and an unrelated patient referred for evaluation and found to have cytochrome c oxidase deficiency.

INTERVENTIONS

None.

MEASUREMENTS/MAIN RESULTS

Affected individuals had the characteristic presentation of psychomotor regression, growth deficiency, and lactic acidosis. The severity of the clinical course was found to correlate with the lactate-pyruvate ratio. Two of the infants had evidence, on magnetic resonance imaging, of subacute necrotizing encephalomyelopathy (Leigh disease). The most severely affected child had an unusual presentation of prenatal onset of structural anomalies including glabellar prominence, abnormal hair, loose skin, inguinal hernias, and hypospadias.

CONCLUSIONS

The presentation and clinical course of cytochrome c oxidase deficiency are highly variable and the diagnosis of cytochrome c oxidase deficiency should be considered in all patients with lactic acidosis or subacute necrotizing encephalomyelopathy. Particular consideration should be given to this diagnosis when lactic acidosis is found in a neonate with structural anomalies.

Second-trimester markers of fetal size in schizophrenia: a study of monozygotic twins

OBJECTIVE

Since the second prenatal trimester is the critical period of massive neural cell migration to the cortex, and fingertip dermal cells migrate to form ridges during this same period, the authors sought to determine whether there are differences in fingertip ridge count in pairs of monozygotic twins discordant for schizophrenia, possibly indicating that a prenatal anatomical insult affected the twins differently.

METHOD

The fingertip dermal ridges of 30 pairs of monozygotic twins (23 pairs in which the twins were discordant for schizophrenia and seven pairs in which both twins were normal) were counted by two persons trained in anthropometric research. Intrapair differences in the counts were then measured, and the differences among the pairs of normal twins were compared with the differences among the pairs discordant for schizophrenia.

RESULTS

The twins discordant for schizophrenia had significantly greater absolute intrapair differences in total finger ridge count and significantly greater percent intrapair differences than the normal twins; i.e., their fingerprints were significantly less "twin-like."

CONCLUSIONS

The study suggests that various second-trimester prenatal disturbances in the epigenesis of one twin in a pair discordant for schizophrenia may be related to the fact that only one of the twins expresses his or her genetic predisposition toward schizophrenia. This is consistent with a "two-strike" etiology of schizophrenia: a genetic diathesis plus a second-trimester environmental stressor.

Pentalogy of Cantrell and ectopia cordis, a familial developmental field complex

The association of sternal fusion defects with various cardiac, diaphragmatic, and anterior body wall defects represents a developmental field complex that includes the Pentalogy of Cantrell and ectopia cordis. No familial cases have been reported previously. We present 3 consecutively born brothers with extensive diaphragmatic defects, 2 who had the Pentalogy of Cantrell. One of the 2 also had ectopia cordis.

Interstitial deletion of chromosome 2q associated with ovarian dysgenesis

In the present report we describe a girl with mental retardation, Dandy-Walker malformation, craniofacial anomalies, cardiac defect, and ovarian dysgenesis associated with an interstitial deletion of chromosome 2. The interstitial deletion in the proband was associated with an apparently balanced translocation involving chromosomes 2 and 7 in the father.

Ovarian dysgenesis in individuals with chromosomal abnormalities

To understand better the pathogenesis of ovarian dysgenesis in individuals with abnormalities such as 45,X Turner syndrome, trisomy 13, and trisomy 18, we have examined microscopically the ovaries of 36 infants with a number of chromosomal abnormalities confirmed by karyotype analysis. All infants with trisomy 13, trisomy 18, triploidy, and 45,X were found to have severe ovarian dysgenesis characterized by a virtual absence of primary oocytes. The ovaries of individuals with 21 trisomy and of those with partial deletion or duplication of an autosome demonstrated variable findings, which ranged from complete absence of oocytes to a mild diminution of oocyte numbers. The results of this study suggest that the attrition of germ cells in these infants is a result of faulty meiotic pairing and that ovarian dysgenesis is a more frequent finding in children with karyotypic abnormalities that has been realized previously.

Craniosynostosis and lid anomalies: report of a girl with Michels syndrome

We report on a 2-year-old girl with Michels syndrome, a condition characterized by mental deficiency, craniosynostosis, blepharophimosis, ptosis, and epicanthus inversus. The phenotypic findings are compared with those of previously reported cases.

Terminal deletions of the long arm of chromosome 7: five new cases

Twenty-two cases of terminal deletions of the long arm of chromosome 7 have been reported. We present 5 new cases, 3 of which were ascertained due to fetal holoprosencephaly, one due to anencephaly, and one due to multiple structural defects in a 15-year-old boy. The presence of holoprosencephaly in 3 of the 5 cases reported herein and in 2 previously reported cases suggests that this manifestation may be commonly observed in individuals with deletion 7q.

Fryns syndrome: an autosomal recessive disorder associated with craniofacial anomalies, diaphragmatic hernia, and distal digital hypoplasia

Fryns syndrome is an autosomal recessive, genetically determined condition with variable expression, which includes abnormal facial features, diaphragmatic hernia, distal limb abnormalities, and malformations of the cardiovascular, gastrointestinal, genitourinary, and central nervous systems. Five cases of children with Fryns syndrome, including an example of familial recurrence and a case of long-term survival, are described. This report brings to 25 the number of cases reported in the literature and further serves to illustrate the clinical variability of this disorder.

Patterns of malformation in children with congenital diaphragmatic defects

The medical records of 102 live-born children with a congenital diaphragmatic defect were reviewed to determine the frequency and nature of underlying chromosomal, genetic, and nongenetic patterns of malformation. Overall, 40 children (39%) had a major nonpulmonary malformation, and 14 of these children (14%) had a previously recognized pattern of malformation. A group of 18 children (18%) with cardiac anomalies had an increased mortality rate in comparison with those children without cardiac defects (72% vs 38%). The frequency and severity of nonpulmonary abnormalities in children with congenital diaphragmatic defects suggest that examination of affected children should include cardiac evaluation, a karyotype when the defect is one feature of a broader pattern of altered development, and a careful evaluation for minor anomalies, which may provide clues to an overall diagnosis.

Oligohydramnios sequence and renal tubular malformation associated with maternal enalapril use

We present the case of a child who died of pulmonary hypoplasia as a result of the oligohydramnios sequence. The mother was taking enalapril, as well as propranolol and hydrochlorothiazide, for treatment of hypertension associated with systemic lupus erythematosus. Autopsy examination revealed severe renal tubular malformation. Correlation of animal data with previous case reports of neonatal anuria in association with maternal angiotensin converting enzyme inhibitors suggests that these agents may have a deleterious effect on fetal renal development and general well-being.

Laterality defects in conjoined twins: implications for normal asymmetry in human embryogenesis

We evaluated six pairs of conjoined twins: four pairs were dicephalus, and two were of the ischiopagus type. In three of the four dicephalus pairs, the right twin had an abnormality of laterality that included a right aortic arch, reversed great vessel orientation, bilateral right-sided isomerism of the lungs, asplenia, and situs inversus of the viscera. The left twin had normal great vessel orientation and situs solitus in each case. The finding that was unique in these three dicephalus twin pairs was their fused hearts, which were similar in orientation and configuration. The fourth dicephalus twin pair had one normally rotated heart, which was located in the midline and had normally placed chambers and great vessels. Each twin of this pair had normal visceral situs. In the two pairs of ischiopagus twins, each pair had two separate hearts, with normal cardiac structure and great vessel relationships. The viscera expressed normal laterality. Documentation of a defect in laterality in the right twin in three conjoined twin pairs with fusion of the hearts, combined with the presence of normal laterality in three pairs without cardiac fusion, has implications regarding the mechanisms leading to laterality of the human embryo. We suggest that rotation of the heart initiates the embryo's process of lateralization and that the laterality defects of the viscera seen in the right twin are a result of their abnormal cardiac rotation.

Autosomal dominant benign neonatal seizures

Eight individuals in two generations of a family experienced seizures neonatally or in early infancy. Evaluation in two of these infants documented an EEG pattern suggestive of seizure activity without discernible pathogenesis of their seizures. Subsequently, affected individuals had a normal neurodevelopmental outcome, although one person had later epilepsy. The benign course of this disorder and its association with adult epilepsy agree with previously reported cases from the literature.

How automatic are social judgments?

Do people infer personality dispositions automatically when they encode behavior? Tulving's encoding-specificity paradigm was adapted to test three operational indicants of automatism: absence of intention, of interference from other mental activity, and of awareness. Recruited for a digit-recall study, subjects read sentences describing actions during the retention interval of either an easy or a difficult digit recall task. Later, sentence recall was cued by (a) disposition cues, (b) strong semantic associates to the sentence actor, or (c) words representing the gist of the sentence, or (d) sentence recall was not cued. Awareness was measured immediately after the last sentence was read. Disposition-cued recall was higher than (b) or (d) and was unaffected by digit recall difficulty. Awareness of making dispositional inferences was only weakly correlated with disposition-cued recall. Results suggest that disposition inferences occurred at encoding, without intention, without interference by differential drain on processing capacity, and with little awareness. Thus, making dispositional inferences seems to be largely, but not entirely, automatic.

How automatic are social judgments?

Do people infer personality dispositions automatically when they encode behavior? Tulving's encoding-specificity paradigm was adapted to test three operational indicants of automatism: absence of intention, of interference from other mental activity, and of awareness. Recruited for a digit-recall study, subjects read sentences describing actions during the retention interval of either an easy or a difficult digit recall task. Later, sentence recall was cued by (a) disposition cues, (b) strong semantic associates to the sentence actor, or (c) words representing the gist of the sentence, or (d) sentence recall was not cued. Awareness was measured immediately after the last sentence was read. Disposition-cued recall was higher than (b) or (d) and was unaffected by digit recall difficulty. Awareness of making dispositional inferences was only weakly correlated with disposition-cued recall. Results suggest that disposition inferences occurred at encoding, without intention, without interference by differential drain on processing capacity, and with little awareness. Thus, making dispositional inferences seems to be largely, but not entirely, automatic.