Four-year prospective clinical trial of agalsidase alfa in children with Fabry disease.

OBJECTIVES: To investigate a 4-year prospective clinical trial of agalsidase alfa in children with Fabry disease, an X-linked metabolic disorder caused by a deficiency of the lysosomal enzyme alpha-galactosidase A. STUDY DESIGN: Seventeen (16 boys, 1 girl; age range, 7.3 to 18.4 years) of the 24 children who completed a 6-month, open-label agalsidase alfa study enrolled in a 3.5-year extension study that investigated the safety and potential efficacy of long-term treatment. All 17 patients completed the initial 6-month study, and 10 patients (9 boys) completed the extension study. RESULTS: Agalsidase alfa was well tolerated. In treated boys, there were sustained, statistically-significant improvements in the clinical features of Fabry disease, including reduced plasma globotriaosylceramide levels, reduced pain severity assessed by the Brief Pain Index, and improved heart rate variability. Mean urine globotriaosylceramide levels were reduced to normal range (P < .05 compared with baseline during 1.5 to 4 years). Kidney function and left ventricular mass indexed to height remained stable throughout. CONCLUSIONS: This clinical trial demonstrates that treatment with agalsidase alfa was well tolerated and associated with improvement of Fabry disease-related features.

Diagnostic criteria and tumor screening for individuals with isolated hemihyperplasia.

Isolated hemihyperplasia, formerly termed isolated hemihypertrophy, is a congenital overgrowth disorder associated with an increased risk for embryonal tumors, mainly Wilms tumor and hepatoblastoma. This practice guideline will set forth the diagnostic criteria and tumor screening recommendations for children with isolated hemihyperplasia, based on the best information available. There is clinical overlap between isolated hemihyperplasia with Beckwith-Wiedemann syndrome. The majority of Beckwith-Wiedemann syndrome patients have a molecular abnormality involving the imprinted cluster of genes at 11p15.5. In contrast, the preponderance of isolated hemihyperplasia patients studied have no identified etiology. Tumors have developed in isolated hemihyperplasia patients with and without molecular abnormalities. For this reason, molecular diagnostics are not helpful in identifying the subset of isolated hemihyperplasia patients with tumor risk and all isolated hemihyperplasia patients should undergo tumor screening.

Whorl patterns on the lower lip are associated with nonsyndromic cleft lip with or without cleft palate.

Nonsyndromic cleft lip with or without cleft palate (CL/P) is a common birth defect due to both genetic and environmental factors. Whorl lip print patterns are circular grooves on the central upper lip and/or the left and right lower lip. To determine if whorls are more common in families with CL/P than in controls, the Pittsburgh Orofacial Cleft Study collected lip prints from over 450 subjects, that is, individuals with CL/P, their relatives, and unrelated controls-from the U.S., Argentina, and Hungary. Using a narrow definition of lower-lip whorl, the frequency of whorls in the U.S. sample was significantly elevated in cleft individuals and their family members, compared to unrelated controls (14.8% and 13.2% vs. 2.3%; P = 0.003 and 0.001, respectively). Whorls were more frequent in CL/P families from Argentina than in CL/P families from the U.S. or Hungary. If these results are confirmed, whorl lip print patterns could be part of an expanded phenotypic spectrum of nonsyndromic CL/P. As such, they may eventually be useful in a clinical setting, allowing recurrence risk calculations to incorporate individual phenotypic information in addition to family history data.

AXIS inhibition protein 2, orofacial clefts and a family history of cancer.

BACKGROUND: Cancer and congenital malformations occasionally may have a common etiology. The authors investigated whether families with one or more members affected by orofacial clefts (that is, families segregating orofacial clefts) had an increased cancer incidence when compared with control families. METHODS: The authors assessed 75 white families with nonsyndromic cleft lip with or without cleft palate (CL/P) and 93 white control families regarding a history of cancer. They used chi(2) and Fisher exact tests to determine significant differences. They then performed molecular studies with genes in which mutations have been independently associated with both cancer and craniofacial anomalies in a total of 111 families with CL/P. RESULTS: The families with CL/P reported a family history of cancer more often than did control families (P <.001), and they had higher rates of specific cancer types: colon (P <.001), brain (P = .003), leukemia (P = .005), breast (P = .009), prostate (P = .01), skin (P = .01), lung (P = .02) and liver (P = .02). The authors detected overtransmission of AXIS inhibition protein 2 (AXIN2) in CL/P probands (P = .003). CONCLUSION: Families segregating CL/P may have an increased susceptibility to cancer, notably colon cancer. Furthermore, AXIN2, a gene that when mutated increases susceptibility to colon cancer, also is associated with CL/P. CLINICAL IMPLICATIONS: People who are at a higher risk of developing disease need to adopt a healthier lifestyle, including avoiding exposure to risk factors that may interact with their genotypes.

Development and validation of a measure of dysmorphology: useful for autism subgroup classification.

Autism spectrum disorders (ASD) comprise a class of neurodevelopmental disorders that can originate from a variety of genetic and environmental causes. To delineate autism's heterogeneity we have looked for biologically-based phenotypes found in consistent proportions of ASD individuals. One informative phenotype is that of generalized dysmorphology, based on whole body examinations by medical geneticists trained in the nuances of anomalous embryologic development. We identified a need for a dysmorphology measure that could be completed by medical clinicians not extensively trained in dysmorphology that would still retain the level of sensitivity and specificity of the comprehensive dysmorphology examination. Based on expert-derived consensus dysmorphology designation of 222 autism patients and a classification validation study of 30 subjects by four dysmorphologists, we determined that dysmorphology designations based on body areas provided superior inter-rater reliability. Using 34 body area designations, we performed a classification and regression tree (CART) analysis to construct a scoring algorithm. Compared to the consensus classification, the model performed with 81% sensitivity and 99% specificity, and classification of a replication dataset of 31 ASD individuals performed well, with 82% sensitivity and 95% specificity. The autism dysmorphology measure (ADM) directs the clinician to score 12 body areas sequentially to arrive at a determination of "dysmorphic" or "nondysmorphic." We anticipate the ADM will permit clinicians to differentiate accurately between dysmorphic and nondysmorphic individuals-allowing better diagnostic classification, prognostication, recurrence risk assessment, and laboratory analysis decisions-and research scientists to better define more homogeneous autism subtypes.

A deletion of proximal 20p inherited from a normal mosaic carrier mother in a newborn with panhypopituitarism and craniofacial dysmorphism.

We describe a newborn male with a constitutional deletion of proximal chromosome 20p involving band p11.2. The phenotype included panhypopituitarism, craniofacial dysmorphism, a small phallus with a semi bifid scrotum, and bilateral widely separated first and second toes. The deletion was inherited from his mother, a mosaic carrier of the same deletion in peripheral lymphocytes. The only other similar case with a deletion of 20p11.22-p11.23 exhibited a phenotype that also included abnormal neural development (autism, craniofacial dysmorphism, and Hirschsprung disease). Our patient expands the spectrum of neurodevelopmental abnormalities associated with haploinsufficiency of band 20p11.2, and is the second deletion of 20p inherited from a normal mosaic carrier mother.

Amino acid clearance during acute metabolic decompensation in maple syrup urine disease treated with continuous venovenous hemodialysis with filtration.

OBJECTIVE: Assessment of amino acid clearances by continuous venovenous hemodialysis with filtration in treatment of a metabolic decompensation in acute maple syrup urine disease. DESIGN: Single patient assessment. SETTING: Pediatric intensive care unit. PATIENTS: A 10-yr-old male with known maple syrup urine disease (branched chain alpha-ketoacid dehydrogenase deficiency) with metabolic decompensation due to an acute viral illness, characterized by altered mental status, progressive obtundation, and severe acidosis. INTERVENTIONS: Continuous venovenous hemodialysis with filtration. MEASUREMENTS AND MAIN RESULTS: Continuous venovenous hemodialysis with filtration was instituted with both filtration (500 mL/m(2)/hr) and dialysis (1000 mL/m(2)/hr) utilized, allowing rapid correction of systemic ketoacidosis while providing amino acid clearance. Amino acid clearance was measured at initiation and at 24 hrs into therapy. The procedure was well tolerated, with near normal mental status within 12 hrs and resumption of enteral feedings. During the 24-hr period of continuous venovenous hemodialysis with filtration, serum leucine levels fell from 2352 to 381 micromoles/L, isoleucine fell from 626 to 164, and valine fell from 1117 to 228. Leucine, isoleucine, and valine clearance rates averaged 13.1, 12.8, and 13.2 mL/min, respectively, and were constant during the 24 hrs of treatment. Clearance of other amino acids during this period did not vary significantly between cationic, anionic, neutral, or hydrophobic amino acids. CONCLUSIONS: Continuous venovenous hemodialysis with filtration provides an effective therapeutic alternative to intermittent hemodialysis during acute metabolic decompensation in maple syrup urine disease.

Orbicularis oris muscle defects as an expanded phenotypic feature in nonsyndromic cleft lip with or without cleft palate.

Nonsyndromic cleft lip+/-cleft palate is a complex disease with a wide phenotypic spectrum; occult defects of the superior orbicularis oris muscle may represent the mildest subclinical form of the lip portion of the phenotype. This study used high-resolution ultrasonography to compare the frequency of discontinuities in the OO muscle in 525 unaffected relatives of individuals with nonsyndromic cleft lip+/-cleft palate versus 257 unaffected controls. OO muscle discontinuities were observed in 54 (10.3%) of the non-cleft relatives, compared to 15 (5.8%) of the controls-a statistically significant increase (P=0.04). Male relatives had a significantly higher rate of discontinuities than male controls (12.0% vs. 3.2%; P=0.01); female relatives also had a higher rate of discontinuities than female controls, but the increase was not statistically significant (8.9% vs. 7.4%; P=0.56). These data confirm the hypothesis that subepithelial OO muscle defects are a mild manifestation of the cleft lip phenotype. Identification of subepithelial OO muscle defects may be important in a clinical setting, as a means of providing more accurate recurrence risk estimates to relatives in cleft families. Furthermore, the expansion of the cleft lip+/-cleft palate phenotypic spectrum should improve the power of genetic studies.

Anthropometric precision and accuracy of digital three-dimensional photogrammetry: comparing the Genex and 3dMD imaging systems with one another and with direct anthropometry.

A variety of commercially available three-dimensional (3D) surface imaging systems are currently in use by craniofacial specialists. Little is known, however, about how measurement data generated from alternative 3D systems compare, specifically in terms of accuracy and precision. The purpose of this study was to compare anthropometric measurements obtained by way of two different digital 3D photogrammetry systems (Genex and 3dMD) as well as direct anthropometry and to evaluate intraobserver precision across these three methods. On a sample of 18 mannequin heads, 12 linear distances were measured twice by each method. A two-factor repeated measures analysis of variance was used to test simultaneously for mean differences in precision across methods. Additional descriptive statistics (e.g., technical error of measurement [TEM]) were used to quantify measurement error magnitude. Statistically significant (P < 0.05) mean differences were observed across methods for nine anthropometric variables; however, the magnitude of these differences was consistently at the submillimeter level. No significant differences were noted for precision. Moreover, the magnitude of imprecision was determined to be very small, with TEM scores well under 1 mm, and intraclass correlation coefficients ranging from 0.98 to 1. Results indicate that overall mean differences across these three methods were small enough to be of little practical importance. In terms of intraobserver precision, all methods fared equally well. This study is the first attempt to simultaneously compare 3D surface imaging systems directly with one another and with traditional anthropometry. Results suggest that craniofacial surface data obtained by way of alternative 3D photogrammetric systems can be combined or compared statistically.

The Pittsburgh Oral-Facial Cleft study: expanding the cleft phenotype. Background and justification.

The Pittsburgh Oral-Facial Cleft study was begun in 1993 with the primary goal of identifying genes involved in nonsyndromic orofacial clefts in a variety of populations worldwide. Based on the results from a number of pilot studies and preliminary genetic analyses, a new research focus was added to the Pittsburgh Oral-Facial Cleft study in 1999: to elucidate the role that associated phenotypic features play in the familial transmission patterns of orofacial clefts in order to expand the definition of the nonsyndromic cleft phenotype. The purpose of this paper is to provide a comprehensive review of phenotypic features associated with nonsyndromic orofacial clefts. These features include fluctuating and directional asymmetry, non-right-handedness, dermatoglyphic patterns, craniofacial morphology, orbicularis oris muscle defects, dental anomalies, structural brain and vertebral anomalies, minor physical anomalies, and velopharyngeal incompetence.

Increased MECP2 gene copy number as the result of genomic duplication in neurodevelopmentally delayed males.

PURPOSE: Mutations in the MECP2 gene are associated with Rett syndrome, an X-linked mental retardation disorder in females. Mutations also cause variable neurodevelopmental phenotypes in rare affected males. Recent clinical testing for MECP2 gene rearrangements revealed that entire MECP2 gene duplication occurs in some males manifesting a progressive neurodevelopmental syndrome. METHODS: Clinical testing through quantitative DNA methods and chromosomal microarray analysis in our laboratories identified seven male patients with increased MECP2 gene copy number. RESULTS: Duplication of the entire MECP2 gene was found in six patients, and MECP2 triplication was found in one patient with the most severe phenotype. The Xq28 duplications observed in these males are unique and vary in size from approximately 200 kb to 2.2 Mb. Three of the mothers who were tested were asymptomatic duplication carriers with skewed X-inactivation. In silico analysis of the Xq28 flanking region showed numerous low-copy repeats with potential roles in recombination. CONCLUSIONS: These collective data suggest that increased MECP2 gene copy number is mainly responsible for the neurodevelopmental phenotypes in these males. These findings underscore the allelic and phenotypic heterogeneity associated with the MECP2 gene and highlight the value of molecular analysis for patient diagnosis, family members at risk, and genetic counseling.

LIT1 and H19 methylation defects in isolated hemihyperplasia.

We performed LIT1 and H19 methylation studies on 27 children with isolated hemihyperplasia (IH). Eight children (29.6%) had a defect in methylation of one or both of these alleles, supporting our hypothesis that these epigenetic changes can result in a phenotype distinct from typical Beckwith-Wiedemann syndrome.

Sialic acid storage disease of the Salla phenotype in American monozygous twin female sibs.

Salla disease, one of three disease phenotypes that manifest increased urinary excretion of unconjugated sialic acid, is an autosomal recessive condition caused by a mutation in SLC17A5. This gene encodes sialin, a lysosomal membrane transporter for sialic acid. Salla disease is rare outside of individuals of Finnish ancestry. In this report we describe the disorder in non-Finnish monozygous twin siblings, the first reported American cases of Salla disease.