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BACKGROUND Delays in the diagnosis of genetic syndromes are common, particularly in low and middle-income countries with limited access to genetic screening services. We, therefore, aimed to develop and evaluate a machine learning-based screening technology using facial photographs to evaluate a child's risk of presenting with a genetic syndrome for use at the point of care. METHODS In this retrospective study, we developed a facial deep phenotyping technology based on deep neural networks and facial statistical shape models to screen children for genetic syndromes. We trained the machine learning models on facial photographs from children (aged

Down syndrome is a common chromosome disorder affecting all body systems. This creates unique physiologic concerns that can affect safety during anesthesia and surgery. Little consensus exists, however, on the best way to evaluate children with Down syndrome in preparation for surgery. We review a number of salient topics affecting these children in the perioperative period, including cervical spine instability, cardiovascular abnormalities, pulmonary hypertension, upper airway obstruction, hematologic disturbances, prematurity, low birth weight, and the use of supplements and alternative therapies. Recommendations include obtaining a complete blood count to detect an increased risk for bleeding or stroke, and cardiology evaluation to identify patients with pulmonary hypertension, as well as undiagnosed or residual heart disease. Pediatric cardiac anesthesiologists and intensivists should be involved as needed. The potential for cervical spine instability should be considered, and the anesthesiologist may wish to have several options available both for the medications and equipment used. The child's family should always be asked if he or she is on any nutritional supplements, as some products marketed to families may have secondary effects such as inhibition of platelet function. Using this evaluation in presurgical planning will allow physicians to better consider the individual circumstances for their patients with Down syndrome. Our goal was to optimize patient safety by choosing the most appropriate setting and perioperative personnel, and to mitigate those risk factors amenable to intervention.

Neurofibromatosis type 1 (NF1), one of the most common genetic disorders with an estimated prevalence of 1:3000 live births, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and an in-frame 1-amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 patients (129 unrelated probands and 33 affected relatives) carrying a constitutional missense mutation affecting one of five neighboring NF1 codons Leu844, Cys845, Ala846, Leu847 and Gly848, located in the Cysteine-Serine-Rich Domain (CSRD). These recurrent missense mutations affect ~0.8% of unrelated NF1 mutation-positive probands in the UAB cohort. A substantial fraction of these patients presented with a severe phenotype, including plexiform and/or spinal neurofibromas, symptomatic optic pathway gliomas, malignant neoplasms or osseous lesions. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent compared with classic NF1 cohorts (both p

Noonan syndrome (NS) and related disorders, such as NS with multiple lentigines (formerly called LEOPARD syndrome), cardiofaciocutaneous syndrome, and Costello syndrome, constitute an important group of developmental malformation syndromes with variable clinical and molecular features. Their underlying pathophysiologic mechanism involves dysregulation of the Ras/mitogen-activated protein kinase signaling pathway, an essential mediator of developmental and growth processes in the prenatal and postnatal setting. Malignant tumor development is an important complication encountered in other RASopathies, such as neurofibromatosis type 1, but the neoplastic risks and incidence of malignant tumors are less clearly defined in NS and related disorders of the Noonan spectrum. Malignant tumor development remains an important complication variably seen in the RASopathies and, thus, a clear understanding of the underlying risks is essential for appropriate clinical care in this patient population. This review discusses previously published reports of malignancies in individuals with RASopathies of the Noonan spectrum.

Down syndrome, the most common single cause of human birth defects, produces alterations in physical growth and mental retardation. If missed before birth, the early detection of Down syndrome is crucial for the management of patients and disease. However, the diagnostic accuracy for pediatricians prior to cytogenetic results is moderate and the access to specialists is limited in many social and low-economic areas. In this study, we propose a simple, non-invasive and automated framework for Down syndrome detection based on disease-specific facial patterns. Geometric and local texture features are extracted based on automatically detected anatomical landmarks to describe facial morphology and structure. To accurately locate the anatomical facial landmarks, a hierarchical constrained local model using independent component analysis (ICA) is proposed. We also introduce a data-driven ordering method for selecting dominant independent components in ICA. The hierarchical structure of the model increases the accuracy of landmark detection by fitting separate models to different groups. Then the most representative features are selected and we also demonstrate that they match clinical observations. Finally, a variety of classifiers are evaluated to discriminate between Down syndrome and healthy populations. The best performance achieved 0.967 accuracy and 0.956 F1 score using combined features and linear discriminant analysis. The method was also validated on a dataset with mixed genetic syndromes and high performance (0.970 accuracy and 0.930 F1 score) was also obtained. The promising results indicate that our method could assist in Down syndrome screening effectively in a simple, non-invasive way, and extensible to detection of other genetic syndromes.

SOX5 encodes a transcription factor involved in the regulation of chondrogenesis and the development of the nervous system. Despite its important developmental roles, SOX5 disruption has yet to be associated with human disease. We report one individual with a reciprocal translocation breakpoint within SOX5, eight individuals with intragenic SOX5 deletions (four are apparently de novo and one inherited from an affected parent), and seven individuals with larger 12p12 deletions encompassing SOX5. Common features in these subjects include prominent speech delay, intellectual disability, behavior abnormalities, and dysmorphic features. The phenotypic impact of the deletions may depend on the location of the deletion and, consequently, which of the three major SOX5 protein isoforms are affected. One intragenic deletion, involving only untranslated exons, was present in a more mildly affected subject, was inherited from a healthy parent and grandparent, and is similar to a deletion found in a control cohort. Therefore, some intragenic SOX5 deletions may have minimal phenotypic effect. Based on the location of the deletions in the subjects compared to the controls, the de novo nature of most of these deletions, and the phenotypic similarities among cases, SOX5 appears to be a dosage-sensitive, developmentally important gene.

Many children born with complex childhood illnesses that historically caused early death are now surviving into adulthood with the expectation of leading meaningful and productive lives. They will ultimately need to transition their care from pediatric to adult-centered care. Unfortunately, in the absence of structured programs to guide this transition, there is often delayed or inappropriate care, improper timing of the transfer of care, and undue emotional and financial stress on the patients, their families, and the healthcare system. At its worst, and as frequently happens now, patients are lost to appropriate follow-up. In fact, the number of adults with congenital heart disease (CHD) in the United States is rising exponentially and now exceeds 1 000 000.1,–,7 At least half of these patients may have complex CHD. Fewer than 30% of adults with CHD are seen by appropriate specialized providers. Fewer than 15% of these patients, who are seen in specialty adult CHD (ACHD) clinics, have CHD that is classified as severe.8 Thus, adolescents with CHD constitute a growing population of individuals for whom a well-planned and well-executed “transition process” is essential. The goals of a formal transition program are to prepare young adults for transfer of care. It should provide uninterrupted health care that is patient centered, age and developmentally appropriate, flexible, and comprehensive. It should include age-appropriate education about medical conditions and promote skills in communication, decision making, self-care, and self-advocacy.9,–,13 It should foster greater personal and medical independence and a greater sense of control over health, healthcare decisions, and psychosocial environment. The ultimate goal of a transition program is to optimize the quality of life (QOL), life expectancy, and future productivity of young patients.14 We acknowledge that the development of ideal transition programs is a …

A moment of one of life's greatest joys can instantly turn to heartwrenching anguish when a baby is unexpectedly born with severe birth defects. Parents of children with catastrophic birth defects ...

Kabuki syndrome (KS) is a rare genetic syndrome involving dysmorphic facial features, and reports of intellectual disability (ID). We examined the developmental trajectory of neuropsychological skills in a child with KS (seen at ages 4, 6, 7, 9, and 11). Examination of raw and age-corrected standard scores suggests that language-based skills developed appropriately, but visually based skills slowed and reached a plateau. Executive dysfunction and mood symptoms were also observed. While ID is described as a core feature of KS, some patients may not meet diagnostic criteria for ID, and may be better described as having specific deficits in nonverbal skills. Longitudinal neuropsychological assessment of children with KS and other syndromes associated with ID is warranted to understand the true prevalence of ID versus isolated cognitive impairments.

A range of phenotypes including Greig cephalopolysyndactyly and Pallister-Hall syndromes (GCPS, PHS) are caused by pathogenic mutation of the GLI3 gene. To characterize the clinical variability of GLI3 mutations, we present a subset of a cohort of 174 probands referred for GLI3 analysis. Eighty-one probands with typical GCPS or PHS were previously reported, and we report the remaining 93 probands here. This includes 19 probands (12 mutations) who fulfilled clinical criteria for GCPS or PHS, 48 probands (16 mutations) with features of GCPS or PHS but who did not meet the clinical criteria (sub-GCPS and sub-PHS), 21 probands (6 mutations) with features of PHS or GCPS and oral-facial- digital syndrome, and 5 probands (1 mutation) with nonsyndromic polydactyly. These data support previously identified genotype-phenotype correlations and demonstrate a more variable degree of severity than previously recognized. The finding of GLI3 mutations in patients with features of oral-facial-digital syndrome supports the observation that GLI3 interacts with cilia. We conclude that the phenotypic spectrum of GLI3 mutations is broader than that encompassed by the clinical diagnostic criteria, but the genotype-phenotype correlation persists. Individuals with features of either GCPS or PHS should be screened for mutations in GLI3 even if they do not fulfill clinical criteria. Hum Mutat 31:1142-1154, 2010. (C) 2010 Wiley-Liss, Inc

Muenke syndrome is an autosomal dominant disorder characterized by coronal suture craniosynostosis, hearing loss, developmental delay, carpal and tarsal fusions, and the presence of the Pro250Arg mutation in the FGFR3 gene. Reduced penetrance and variable expressivity contribute to the wide spectrum of clinical findings in Muenke syndrome. To better define the clinical features of this syndrome, we initiated a study of the natural history of Muenke syndrome. To date, we have conducted a standardized evaluation of nine patients with a confirmed Pro250Arg mutation in FGFR3. We reviewed audiograms from an additional 13 patients with Muenke syndrome. A majority of the patients (95%) demonstrated a mild-to-moderate, low frequency sensorineural hearing loss. This pattern of hearing loss was not previously recognized as characteristic of Muenke syndrome. We also report on feeding and swallowing difficulties in children with Muenke syndrome. Combining 312 reported cases of Muenke syndrome with data from the nine NIH patients, we found that females with the Pro250Arg mutation were significantly more likely to be reported with craniosynostosis than males (P < 0.01). Based on our findings, we propose that the clinical management should include audiometric and developmental assessment in addition to standard clinical care and appropriate genetic counseling.

Background The approach to clinical evaluation of the dysmorphic neonate can be challenging and multifaceted. It requires specialized knowledge of rare diagnoses and awareness of immediate versus long-term needs for the newborn and the family. Purpose This review summarizes important considerations in the initial evaluation of genetic syndromes, which can present in the neonatal period with variable aspects of dysmorphism. Methods An overview of the literature in this area is provided. Findings/results Several overlapping areas of concern for working with this population are addressed, including communication with the family, fundamentals of the physical examination, common genetic disorders, syndromes, as well as palliative care and end of life decision making for the newborn in the context of family needs. Implications for practice The initial approach for the neonatal practitioner needs to focus on various aspects of the newborn's care, including medical stabilization, determining whether immediate laboratory or imaging studies are needed, careful physical examination with particular attention to detail, appropriate and timely communication with the family, and knowledge of various specific aspects of rare diseases. Implications for research More research is needed to better understand how to best support the newborn born with dysmorphia or a rare disease. Particular attention needs to be focused on strategies to best support the family who is often in crisis during the neonatal period.

Statistical shape models generally characterize shape variations linearly by principal component analysis (PCA), which assumes that the non-rigid shape parameters are drawn from a Gaussian distribution. This practical assumption is often not valid. Instead, we propose a constrained local model based on independent component analysis (ICA) and use kernel density estimation (KDE) for non-parametrically modeling the distribution of the shape parameters. The model fitting is achieved by maximum a posteriori via the expectation-maximization algorithm and results in a mean shift-like update optimizer. The proposed approach is capable of modeling non-Gaussian shape priors and significantly outperformed the PCA-based model (p=0.03) and ICA-based model with Gaussian shape prior (p=0.01) in experiments to detect facial landmarks. Moreover, we applied the model to Down syndrome detection from frontal facial photographs and obtained higher accuracy than the best results reported in literature.

Purpose: 1) To identify morphometric characteristics in hemizygous patients with Fabry disease a treatable lysosomal storage disorder caused by the deficiency of α-galactosidase A where morphological abnormalities have occasionally been mentioned, but have never been investigated systematically. 2) To devise a quantitative method to evaluate dysmorphic abnormalities in Fabry disease. Method: Cross-sectional, single center, independent dysmorphology assessment by a panel of three clinical geneticists, based on standardized medical photography. Population: consecutive hemizygous patients with Fabry disease (N = 38) unselected for the features assessed, mean age 38 ± 10.8 years (range: 10–60), recruited for neuropathic pain into enzyme replacement therapy trials. Results: The following dysmorphic features were identified (in order of descending frequency): periorbital fullness, prominent lobules of the ears, bushy eyebrows, recessed forehead, pronounced nasal angle, generous nose/bulbous nasal tip, prominent supraorbital ridges, shallow midface, full lips, prominent nasal bridge, broad alar base, coarse features, posteriorly rotated ears, and prognathism. Extremity features included broad fingertips, short fingers, prominent superficial vessels of hands, 5th digit brachydactyly, and 5th digit clinodactyly. Narrow anterior-posterior chest diameter was noted. Ten core features were statistically defined. Cronbach's alpha measuring internal consitency was 0.62. Light's kappa for global inter-rater variability was 0.26 while Cohen's kappa allowing pair-wise rater comparison varied between 0.08–0.48. Conclusions: Patients with Fabry disease share common morphological characteristics of the face, trunk, and extremities. Some of these features are subtle as documented by the inter-rater variability. Awareness of these features may facilitate the diagnosis of patients with Fabry disease, and identification of affected family members.

Down syndrome is the most common chromosomal condition that presents characteristic facial morphology and texture patterns. The early detection of Down syndrome through an automatic, non-invasive and simple way is desirable and critical to provide the best health management to newborns. In this study, we propose such a computer-aided diagnosis system for Down syndrome from photography based on facial analysis with ensemble learning. First, geometric and texture facial features are extracted based on automatically located facial landmarks, followed by feature fusion and selection. Then multiple classifiers (i.e. support vector machines, random forests and linear discriminant analysis) are adopted to identify patients with Down syndrome. An accurate and reliable decision is finally achieved by optimally combining the outputs of these individual classifiers via ensemble learning that captures both the shared and complementary information from different classifiers. The best performance was achieved by using the median ensemble rule with 0.967 accuracy, 0.977 precision and 0.933 recall.

The occurrence of unexpected fractures in children is one of the most distressing and complex medical situations faced by patients, their families and medical professionals. Medical providers often must make decisions based upon incomplete, erroneous and/or false history as given by the caretaker. The number of child and adolescent victims of child abuse in the United States was estimated at 681,000 in 2011 (US Department of Health and Human Services; Child Maltreatment 2010) [U.S. Department of Health and Human Services, Administration for Children and Families, Administration on Children, Youth and Families, Children’s Bureau. Child Maltreatment 2010 ( http://www.acf.hhs.gov/programs/cb/stats_research/index.htm#can )]. Physical abuse was reported in 17% of these cases, while 27% of these children were 2 years of age or younger, many of whom were nonverbal. As a result, an increasing number of caretakers who are investigated for inflicting these types of injuries are offering osteogenesis imperfecta as a defense to the allegations. Physicians should consider the possibility of metabolic bone disease, including osteogenesis imperfecta, as a cause of injury in this group of patients. The goal of this chapter is to provide both primary care physicians and pediatric specialists with useful information that will allow for a logical approach to the diagnosis and management of the patient with skeletal trauma.

Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been reported. Such chromosome number abnormalities are almost universally fatal early in gestation or in infancy. Clinical features of specific chromosome number abnormalities may be recognized by phenotypic manifestations in addition to the HPE.

In addition to craniofacial, auricular, ophthalmologic, and oral anomalies, the distinctive phenotype of the branchio-oculo-facial (BOF) syndrome (MIM 113620) includes skin defects in the neck or infra/supra-auricular region. These unusual areas of thin, erythematous wrinkled skin differ from the discrete cervical pits, cysts, and fistulas of the branchio-oto-renal (BOR) syndrome (MIM 113650). Although the BOF and BOR syndromes are sufficiently distinctive that they should not be confused, both can be associated with nasolacrimal duct stenosis, deafness, prehelical pits, malformed pinna, and renal anomalies. Furthermore, a reported father and son [Legius et al., 1990, Clin Genet 37:347-500] had features of both conditions. It was not clear whether they had an atypical presentation of either BOR or BOF syndrome, or represented a private syndrome. In light of these issues, we selected the BOR locus (EYA1) as a possible gene mutation for the BOF syndrome. In five BOF patients, there were no mutations detected in the EYA1 gene, suggesting that it is not allelic to the BOR syndrome.

Acampomelic campomelic dysplasia (ACD) is a rare genetic syndrome affecting bone and connective tissue. This syndrome is a variant of the more commonly encountered campomelic dysplasia but is characterized by the absence of long bone curvature (acampomelia). Affected children have a characteristically flat facial profile and present with respiratory distress. They all have markedly hypoplastic scapulae. We present two sisters with ACD between whom there were some clinical and radiographic differences and also variations from the classic CD. We describe shallow orbits, a radiographic finding that has not been previously documented in this dysplasia.

Down syndrome is the most commonly occurring chromosomal condition; one in every 691 babies in United States is born with it. Patients with Down syndrome have an increased risk for heart defects, respiratory and hearing problems and the early detection of the syndrome is fundamental for managing the disease. Clinically, facial appearance is an important indicator in diagnosing Down syndrome and it paves the way for computer-aided diagnosis based on facial image analysis. In this study, we propose a novel method to detect Down syndrome using photography for computer-assisted image-based facial dysmorphology. Geometric features based on facial anatomical landmarks, local texture features based on the Contourlet transform and local binary pattern are investigated to represent facial characteristics. Then a support vector machine classifier is used to discriminate normal and abnormal cases; accuracy, precision and recall are used to evaluate the method. The comparison among the geometric, local texture and combined features was performed using the leave-one-out validation. Our method achieved 97.92% accuracy with high precision and recall for the combined features; the detection results were higher than using only geometric or texture features. The promising results indicate that our method has the potential for automated assessment for Down syndrome from simple, noninvasive imaging data.

Conventional statistical shape models use Principal Component Analysis (PCA) to describe shape variations. However, such a PCA-based model assumes a Gaussian distribution of data. A model with Independent Component Analysis (ICA) does not require the Gaussian assumption and can additionally describe the local shape variation. In this paper, we propose a Hierarchical Constrained Local Model (HCLM) using ICA. The first or coarse level of HCLM locates the full landmark set, while the second level refines a relevant landmark subset. We then apply the HCLM to Down syndrome detection from photographs of young pediatric patients. Down syndrome is the most common chromosomal condition and its early detection is crucial. After locating facial anatomical landmarks using HCLM, geometric and local texture features are extracted and selected. A variety of classifiers are evaluated to identify Down syndrome from a healthy population. The best performance achieved 95.6% accuracy using support vector machine with radial basis function kernel. The results show that the ICA-based HCLM outperformed both PCA-based CLM and ICA-based CLM.

Conventional cytogenetics is a useful clinical tool that has a lower limit of sensitivity of 2–5 Mb for detection of duplications of deletions. Because the threshold of clinically significant aneusomy is below this range, there is a need for approaches to improve the sensitivity of the detection of aneusomy. We have implemented a system of screening for subtle unbalanced translocations in children with multiple congenital anomalies of unkonwn cause. Our approach uses subtelomeric microsatellite markers to detect small areas of segmental aneusomy due to unbalanced translocations. Herein we report a patient with severe multiple congenital anomalies and a normal karyotype who was diagnosed by this approach. Microsatellite markers from 41 telomeres were analyzed and were normal with the exception of those on distal chromosome 22. Further analysis with additional microsatellites and fluorescent in in situ hybridization confirmed duplication of 22q13.2-qter. We conclude that microsatellite screening can detect subtle unbalanced translocations in children with severe anomalies. © 1995 Wiley-Liss, Inc.

Marfanoid phenotype with craniosynostosis (Shprintzen-Goldberg syndrome) is a rare disorder previously described in only 5 patients. We report on the sixth known patient with this condition. The findings which distinguish our patient from others reported previously are that she was ascertained prenatally as having a cloverleaf skull; this is the first female patient described with this condition. Postnatally, she presented with arachnodactyly, camptodactyly, and clover-leaf skull. Imaging studies of the brain documented microcephaly with malformed brain, hydrocephaly, and hypoplasia of the corpus callosum. She also had choanal atresia and stenosis, a clinical finding previously reported only once, in this disorder.

Genetic epidemiological evidence suggests that mutations in BRCA1 may be responsible for approximately one half of early onset familial breast cancer and the majority of familial breast/ovarian cancer. The recent cloning of BRCA1 allows for the direct detection of mutations, but the feasibility of presymptomatic screening for cancer susceptibility is unknown. We analyzed genomic DNA from one affected individual from each of 24 families with at least three cases of ovarian or breast cancer, using SSCP assays. Variant SSCP bands were subcloned and sequenced. Allele-specific oligonucleotide hybridization was used to verify sequence changes and to screen DNA from control individuals. Six frameshift and two missense mutations were detected in 10 different families. A frameshift mutation was detected in a male proband affected with both breast and prostate cancer. A 40-bp deletion was detected in a patient who developed intra-abdominal carcinomatosis 1 year after prophylactic oophorectomy. Mutations were detected throughout the gene, and only one was detected in more than a single family. These results provide further evidence that inherited breast and ovarian cancer can occur as a consequence of a wide array of BRCA1 mutations. These results suggests that development of a screening test for BRCA1 mutations will be technically challenging. The finding of a mutation in a family with male breast cancer, not previously thought to be related to BRCA1, also illustrates the potential difficulties of genetic counseling for individuals known to carry mutations.

We review 43 patients (15 new, 28 literature) with the branchio-oculo-facial (BOF) syndrome, which has a distinctive phenotype ranging from mild to severe forms, consisting of eye, ear, oral, and craniofacial anomalies. Virtually ubiquitous and possibly pathognomonic are the cervical/infra-auricular skin defects. Much less common are supra-auricular defects occurring as isolated anomalies or with cervical defects. Regardless of location, these lesions may have aplastic, “hemangiomatous,” or otherwise abnormal overlying skin, and draining sinus fistulae. Renal malformations are frequent, but congenital heart and central nervous system defects are rare. Psychomotor performance is usually normal, but development delays, hypotonia, and visual, hearing, and speech problems are common. Autoso-mal dominant inheritance seems likely. Overlap between the BOF and branchio-oto-renal syndromes has been observed, but elucidation of its molecular basis is not yet available. This article also discusses 5 patients with atypical manifestations considered to be possibly affected or probably unaffected, who are sufficiently unusual to be excluded from the final data analysis. © 1995 Wiley-Liss, Inc.

Background Chromosome 15q24 microdeletion syndrome is a rare genomic disorder characterised by intellectual disability, growth retardation, unusual facial morphology and other anomalies. To date, 20 patients have been reported; 18 have had detailed breakpoint analysis. Aim To further delineate the features of the 15q24 microdeletion syndrome, the clinical and molecular characterisation of fifteen patients with deletions in the 15q24 region was performed, nearly doubling the number of reported patients. Methods Breakpoints were characterised using a custom, high-density array comparative hybridisation platform, and detailed phenotype information was collected for each patient. Results Nine distinct deletions with different breakpoints ranging in size from 266 kb to 3.75 Mb were identified. The majority of breakpoints lie within segmental duplication (SD) blocks. Low sequence identity and large intervals of unique sequence between SD blocks likely contribute to the rarity of 15q24 deletions, which occur 8–10 times less frequently than 1q21 or 15q13 microdeletions in our series. Two small, atypical deletions were identified within the region that help delineate the critical region for the core phenotype in the 15q24 microdeletion syndrome. Conclusion The molecular characterisation of these patients suggests that the core cognitive features of the 15q24 microdeletion syndrome, including developmental delays and severe speech problems, are largely due to deletion of genes in a 1.1–Mb critical region. However, genes just distal to the critical region also play an important role in cognition and in the development of characteristic facial features associated with 15q24 deletions. Clearly, deletions in the 15q24 region are variable in size and extent. Knowledge of the breakpoints and size of deletion combined with the natural history and medical problems of our patients provide insights that will inform management guidelines. Based on common phenotypic features, all patients with 15q24 microdeletions should receive a thorough neurodevelopmental evaluation, physical, occupational and speech therapies, and regular audiologic and ophthalmologic screening.

In a neurofibromatosis type 1 murine model, treatment with lovastatin reversed cognitive disabilities. We report on a phase I study examining the safety and tolerability of lovastatin in children with neurofibromatosis type 1. Twenty-four children with neurofibromatosis type 1 underwent a dose-escalation protocol for 3 months to identify the maximum tolerated dose and potential toxicity. Minimal side effects were evident, and no child experienced dose-limiting toxicity. Cognitive evaluations were completed before and after treatment, and the results suggested improvement in areas of verbal and nonverbal memory. Additional analyses, using reliable change indices, indicated improvements exceeding those of test-retest or practice effects in some participants. These observations may be analogous to the improvements observed in a neurofibromatosis type 1 murine model treated with lovastatin, although further study and replication are required. The safety and preliminary cognitive results support the need for a larger phase II trial in this population.

We report on 2 Mennonite sisters with a syndrome of sparse hair, osteopenia, mental retardation, minor facial abnormalities, joint laxity, and hypotonia. Their asymptomatic consanguineous parents (inbreeding coefficient F = 1/64) have 6 other offspring, 3 of whom died in infancy of type II osteogenesis imperfecta (OI), and 3 of whom are normal. We analyzed collagens synthesized by cultured fibroblasts from these 2 sisters and their parents and detected no major abnormalities. Results of chromosomal and metabolic evaluations including amino acid analysis of plasma, urine, and hair were unremarkable. A literature search and survey of a computerized syndrome identification database did not disclose an identical phenotype. The sisters bear superficial resemblance to several known syndromes which we excluded on clinical and/or biochemical grounds. We conclude that they represent a new autosomal recessive syndrome, distinct from type II OI and perhaps unique to the Mennonite population or to this particular family. © 1992 Wiley-Liss, Inc.

Holoprosencephaly (HPE) is the most common malformation of the human forebrain, and may be due to cytogenetic anomalies, teratogens, occur in the context of a syndrome, or be due to mutations in single genes associated with non-syndromic HPE. Mutations in ZIC2, a transcription factor located on chromosome 13q32, are the second-most common cause of non-syndromic, non-chromosomal HPE. Blood samples from over 1000 individuals with HPE-spectrum disorders and their relatives were analyzed for sequence variations in ZIC2. We examined clinical details and included all other known previously published and unpublished cases of mutations in ZIC2 through a literature search and collaboration with other centers. We find mutations in ZIC2 in 8% of probands with HPE, and describe 153 individuals from 116 unrelated kindreds, including 137 patients with molecularly-determined mutations in ZIC2 and 16 patients with deletions of the ZIC2 locus. Unlike HPE due to mutations in other genes, the vast majority of cases are sporadic and the proportional distribution of HPE types differs significantly from previously published analyses of non-chromosomal non-syndromic HPE. Furthermore, we describe a novel facial phenotype in patients with mutations in ZIC2 which includes bitemporal narrowing, upsplanting palpebral fissures, a short nose with anteverted nares, and a broad and well-demarcated philtrum, and large ears. This phenotype is distinct from the standard facial dysmorphisms associated with non-chromosomal, non-syndromic HPE. Our findings show that HPE due to mutations in ZIC2 is distinct from that due to mutations in other genes. This may shed light on the mechanisms that contribute to the formation of the face and the forebrain and may help direct genetic counseling and diagnostic strategies.

Treacher Collins syndrome is an autosomal dominant condition of bilateral craniofacial abnormalities of structures derived from the first and second branchial arches. A patient with severe manifestations of Treacher Collins syndrome and a de novo chromosomal deletion in region 4p15.32----p14 was identified. Anonymous DNA sequences of loci D4S18, D4S19, D4S20, D4S22, and D4S23 were mapped to the deleted region. DNA probes previously mapped to loci on chromosome 4p (D4S10, D4S15, D4S16, D4S26, D4S35, D4S95, D4S144, RAF1P1, QDPR, and HOX7) were not deleted in this patient. Linkage analysis between the D4S18, D4S23, and QDPR loci and Treacher Collins syndrome in eight families excluded the Treacher Collins syndrome locus from the region of the deletion.

A recessive form of severe osteogenesis imperfecta that is not caused by mutations in type I collagen has long been suspected. Mutations in human CRTAP (cartilage-associated protein) causing recessive bone disease have been reported. CRTAP forms a complex with cyclophilin B and prolyl 3-hydroxylase 1, which is encoded by LEPRE1 and hydroxylates one residue in type I collagen, alpha1(I)Pro986. We present the first five cases of a new recessive bone disorder resulting from null LEPRE1 alleles; its phenotype overlaps with lethal/severe osteogenesis imperfecta but has distinctive features. Furthermore, a mutant allele from West Africa, also found in African Americans, occurs in four of five cases. All proband LEPRE1 mutations led to premature termination codons and minimal mRNA and protein. Proband collagen had minimal 3-hydroxylation of alpha1(I)Pro986 but excess lysyl hydroxylation and glycosylation along the collagen helix. Proband collagen secretion was moderately delayed, but total collagen secretion was increased. Prolyl 3-hydroxylase 1 is therefore crucial for bone development and collagen helix formation.

Low-grade gliomas are the most common central nervous system tumor in children.1 Low-grade gliomas that involve the pregeniculate afferent visual pathway are labeled as optic pathway gliomas (OPGs) and histologically are grade 1 pilocytic or, less commonly, grade 2 fibrillary astrocytomas. Optic pathway gliomas are intrinsic to the axons of the visual pathway and not amenable to surgical resection.2 They are often sporadic but may arise in as many as 20% of children with neurofibromatosis type 1 (NF1), a multisystem genetic disorder occurring in approximately 1:4000 births.3 Although children with OPGs have a low mortality rate, with a 5-year survivorship of greater than 75%,1 they have frequent visual morbidity with permanent visual acuity (VA) loss ranging from mild (ie, 20/40) to complete blindness.2,4 The management of young children with OPGs can be complex. Vision loss takes place in many, but not all, of those with sporadic OPGs and in roughly half of children with NF1-related OPGs.5 Therefore, in an attempt to avoid unnecessary chemotherapy, treatment of OPGs is often only initiated once new or progressive VA loss has been detected. Most OPGs cause VA and/or visual field (VF) loss between 1 and 8 years of age.6 Accurately measuring VA/VF in these young children is highly dependent on their cooperation; this can be especially difficult in those with NF1 due to associated cognitive and behavioral problems.7,8 Unfortunately, functional tests, such as visual evoked potentials,9–13 or changes in imaging features (ie, tumor size or contrast enhancement) have no temporal relationship to VA/VF loss.4,6,14 The inability to assess young children for visual deterioration puts them at greater risk to experience significant and permanent visual loss before treatment is initiated. To better guide therapy, a reliable quantitative biomarker of vision that does not rely on patient cooperation is needed in young children with OPGs.6 For more than a decade, the relationship between VF loss and circumpapillary retinal nerve fiber layer (RNFL) thickness, as measured by optical coherence tomography (OCT), has been firmly established in adults with glaucoma.15–17 However, the mechanism of axonal degeneration causing RNFL thinning in glaucoma is clearly different from that implicated in OPGs. Two studies have used time-domain OCT to examine circumpapillary RNFL thickness in older children with OPGs.18,19 Most participants in both studies were older than 8 years of age, when NF1-related OPGs typically are no longer symptomatic. Even in some of these older children, accurate and reliable OCT acquisition could not be accomplished owing to poor cooperation.19 Recently, a number of investigators have used a spectral-domain handheld OCT (HH-OCT; Bioptigen) device to image the retina and optic nerve of infants and young children with a variety of conditions.20–25 The aim of this study was to determine whether measures of circumpapillary RNFL thickness, acquired with HH-OCT during sedation, can differentiate between young children with and without vision loss from OPGs.

We screened 120 children with sporadic multiple congenital anomalies and either growth or mental retardation for uniparental disomy (UPD) or subtelomeric deletions. The screening used short tandem repeat polymorphisms (STRP) from the subtelomeric regions of 41 chromosome arms. Uninformative marker results were reanalyzed by using the next available marker on that chromosome arm. In total, approximately 25,000 genotypes were generated and analyzed for this study. Subtelomeric deletions of 1 Mb in size were excluded for 27 of 40 chromosome arms. Among the 120 subjects none was found to have UPD, but five subjects (4%, 95% confidence interval 1-9%) were found to have a deletion or duplication of one or more chromosome arms. We conclude that UPD is not a frequent cause of undiagnosed multiple congenital anomaly syndrome. In addition, we determined that 9p and 7q harbor chromosome length variations in the normal population. We conclude that subtelomeric marker analysis is effective for the detection of subtelomeric duplications and deletions, although it is labor intensive. Given a detection rate that is similar to prior studies and the large workload imposed by STRPs, we conclude that STRPs are an effective, but impractical, approach to the determination of segmental aneusomy given current technology.

Chromosomal aberrations are a common cause of multiple anomaly syndromes that include developmental and growth retardation. Current microscopic techniques are useful for the detection of such aberrations but have a limit of resolution that is above the threshold for phenotypic effect. We hypothesized that a genomewide microsatellite screen could detect chromosomal aberrations that were not detected by standard cytogenetic techniques in a portion of these individuals. To test this hypothesis, we performed a genomewide microsatellite screen of patients, by use of a currently available genetic-marker panel that was originally designed for meiotic mapping of Mendelian traits. We genotyped approximately 400 markers on 17 pairs of parents and their children who had normal karyotypes. By using this approach, we detected and confirmed two cases of segmental aneusomy among 11 children with multiple congenital anomalies. These data demonstrate that a genomewide microsatellite scan can be used to detect chromosomal aberrations that are not detected by microscopic techniques.

Objective To determine if haploinsufficiency for chromosome 4p16.3 in Wolf-Hirschhorn syndrome (WHS) is associated with cochlear hearing loss. Design Case series. Setting Tertiary care center. Patients Six patients with WHS were identified through a database and charts were retrospectively reviewed. Main Outcome Measures Presence of sensorineural hearing loss as assessed by brainstem auditory evoked response. Results One of the 6 patients had sensorineural hearing loss. Three of the 6 patients had chronic otitis media with effusion and underwent bilateral tympanostomy tube placement; 2 of these 3 had cleft lip and palate, and 1 had a bifid uvula. One of the 6 patients had spontaneous nystagmus. Five of the 6 patients had preauricular and/or auricular abnormalities. Conclusions More than 25 genes for nonsyndromic hereditary hearing impairment have been mapped. One of these genes, DFNA6 , was identified through linkage analysis of a family with dominant, progressive, low-frequency sensorineural hearing loss. DFNA6 maps to chromosome 4p16.3, a region that is partially deleted in patients with WHS. In our series, we identified the second patient with WHS in the literature with bilateral sensorineural hearing loss. The incidence and type of otologic findings are consistent with those reported in the literature. Analysis of patients with chromosomal rearrangements represents one strategy toward identifying candidate genes for genetic hearing impairment.

The Brachmann-de Lange syndrome is a disorder with a high degree of clinical variability, generally associated with moderate to severe mental retardation. To date, 7 previous cases of Brachmann-de Lange syndrome with normal intelligence (IQ > 70) have been described. We report the eighth case of Brachmann-de Lange syndrome with normal intelligence. In reviewing thr literature, consistent clinical menifestations seen in these 8 patients that are of prognostic value are the absence of significant limb anomalies and birth weight > 2,500 g. © 1993 Wiley-Liss, Inc.

We report on a mildly abnormal 5-year-old girl with seizures, psychomotor retardation, and areas of hyperpigmentation who had a super-numerary marker chromosome in fibroblasts which was identified as an i(5p). To our knowledge, this is the first reported case of tetrasomy 5p. She shares in common some, but not all, manifestations of the dup (5p) syndrome. Cytogenetic analysis of relatives showed that the phenotypically apparently normal mother, maternal grandmother, and a brother of the proband also had a marker chromosome in their lymphocytes which was unrelated to the i(5p). © 1993 Wiley-Liss, Inc.

Detailed clinical, ophthalmological, and molecular studies were performed on a multigeneration family in which there were many subjects with type 1 neurofibromatosis, a common autosomal dominant disorder. Affected family members displayed a wide range of clinical findings including, in two subjects, features seen in Noonan syndrome (triangular facies, downward slanting palpebral fissures, micrognathia, short stature, and learning disability). Subjects have been described previously whose features have overlapped with neurofibromatosis and Noonan syndrome, and it has been suggested that these persons might represent a separate condition. DNA haplotype analysis showed linkage of the neurofibromatosis phenotype seen in this family to the proximal long arm of chromosome 17 in the region where the type 1 neurofibromatosis gene has been mapped. These results imply that the Noonan phenotype seen in some patients with type 1 neurofibromatosis might be the result of variable or variant expression of the neurofibromatosis gene on chromosome 17. The possible role of non-specific factors, such as fetal hypotonia, in producing the neurofibromatosis-Noonan phenotype needs further investigation. The availability of closely linked and intragenic molecular markers for neurofibromatosis could potentially be useful in the diagnosis and characterisation of patients and families with atypical forms of neurofibromatosis.

Nat. Genet. 39, 359–365 (2007); published online 4 February 2007; corrected after print 26 June 2008 In the version of this article initially published, the nucleotide positions of the mutations in the LEPRE1 cDNA and genomic DNA sequence in Table 1, Supplementary Table 1 and Supplementary Figure 1 were incorrectly numbered relative to the first nucleotide of exon 1 rather than the first nucleotide of the LEPRE1 start codon.

The authors report the ocular findings in a patient with partial trisomy 3 [46, XY-15, der(15), t(3;15) (q26;128) mat] and review the literature on this chromosomal anomaly. The patient's main ocular finding was infantile glaucoma. The patient's mother was phenotypically normal and carried a balanced chromosome translocation. Awareness of the ocular abnormalities associated with partial trisomy syndromes is essential since more children with these syndromes survive today than in the past.

• Pericentric inversion of chromosome 11 occurred in consecutive generations of family members with congenital glaucoma. Affected persons were characterized by unilateral or bilateral congenital glaucoma, bilateral corneal disease, and a lack of appreciable dysmorphism. Previous reports of inversions of chromosome 11 are rare, and no ocular abnormalities have been noted. Chromosomal abnormalities may be the cause of some forms of congenital glaucoma and should be included in the genetic heterogeneity of this disease.

Fragile X (or Martin-Bell) syndrome, a common, genetic, mental retardation disorder is increasingly being recognized as a major cause of cognitive disability and psychiatric illness in boys. Here, we present a study in which relatives in 4 generations of a large family with the fra(X) chromosome were given comprehensive psychiatric evaluations in order to further describe the psychopathology associated with this condition. Three of 4 males with the fra(X) chromosome were found to have autistic behavior. An adult fra(X) male had a chronic schizoaffective disorder and mental retardation. In female relatives, a relationship was found between the fra(X) carrier status and psychopathology including schizoaffective and major affective disorders.

Teeth of seven patients from the Brandywine isolate who had dentinogenesis imperfecta (DI) type III were evaluated by clinical, radiologic, and scanning electron microscopic techniques. The deciduous and permanent teeth were opalescent, and there was marked attrition. Enamel pitting was present on some permanent teeth. Anterior open bites were found in all persons with complete permanent dentitions. Pulps of developing teeth were larger than normal during early development but rapidly became almost completely obliterated. There was increased constriction at the cementoenamel junctions. While radiolucencies were noted at the apices of teeth which had pulp exposures due to attrition, several patients had similar radiolucencies which could not be attributed to caries or attrition. Scanning electron microscopy showed a significant reduction in the number of dentin tubules on fractured dentin surfaces; calcospherites at the calcification front were either irregularly shaped or absent. A single tooth from a patient with DI type II was studied and had similar abnormalities on scanning electron microscopy, although tubules were easier to find and calcospherites at the calcification front were more regular than in DI type III. The findings in DI type III of enamel pitting, enlarged pulps early in tooth development, and radiolucencies at the apices of teeth without pulp exposures support the hypothesis that DI type II and DI type III are different disorders.

We have described a previously unrecognized chondrodystrophy characterized by short-limbed dwarfism, blue sclera, severe cardiopulmonary problems, and failure of postnatal growth. The first of two siblings thus affected died at age 6 months following attempted correction of an atrial septal defect. Growth plate cartilage from multiple sites obtained at autopsy showed a marked abnormality of architecture on the light microscopic level. Biochemical studies demonstrated an absence of normal alpha 1(II) collagen in costochondral junction growth plate cartilage and an appearance of the major collagen in a band which comigrates on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with 3 alpha collagen. Cartilage extracted from structural rib appeared to be normal.

Through a multi-center collaboration study, we here report six individuals from five unrelated families, with mutations in KAT6A/MOZ detected by whole-exome sequencing. All five different de novo heterozygous truncating mutations were located in the C-terminal transactivation domain of KAT6A: NM_001099412.1: c.3116_3117 delCT, p.(Ser1039∗); c.3830_3831insTT, p.(Arg1278Serfs∗17); c.3879 dupA, p.(Glu1294Argfs∗19); c.4108G>T p.(Glu1370∗) and c.4292 dupT, p.(Leu1431Phefs∗8). An additional subject with a 0.23 MB microdeletion including the entire KAT6A reading frame was identified with genome-wide array comparative genomic hybridization. Finally, by detailed clinical characterization we provide evidence that heterozygous mutations in KAT6A cause a distinct intellectual disability syndrome. The common phenotype includes hypotonia, intellectual disability, early feeding and oromotor difficulties, microcephaly and/or craniosynostosis, and cardiac defects in combination with subtle facial features such as bitemporal narrowing, broad nasal tip, thin upper lip, posteriorly rotated or low-set ears, and microretrognathia. The identification of human subjects complements previous work from mice and zebrafish where knockouts of Kat6a/kat6a lead to developmental defects.