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S De Bie

Publications and source records attributed to S De Bie.

At least 19 recordsLinked to original sources

Genotype and phenotype analysis of 171 patients referred for molecular study of the fibrillin-1 gene FBN1 because of suspected Marfan syndrome.

BACKGROUND: Marfan syndrome (MFS) is an underrecognized heritable connective tissue disorder resulting from mutations in the gene for fibrillin-1 (FBN1). Affected patients are at risk for aortic dissection and/or severe ocular and orthopedic problems. The diagnosis is primarily based on a set of well-defined clinical criteria (Ghent nosology). The age-related nature of some clinical manifestations and variable phenotypic expression may hinder the diagnosis, particularly in children. Molecular analysis may be helpful to identify at-risk individuals early and start prophylactic medical treatment. FBN1 mutations have also been reported in patients with Marfan-related conditions, but it is unknown what proportion of all FBN1 mutation carriers they represent. METHODS: We reviewed the clinical and molecular data of 171 consecutive patients referred for FBN1 analysis because either MFS was diagnosed or they had signs suggestive of MFS. We compared the incidence of mutations in patients who fulfilled the clinical diagnostic criteria for MFS with those who did not. RESULTS: Diagnostic criteria for MFS were fulfilled in 94 patients, 62 (66%) of whom had an FBN1 mutation. A significantly higher incidence of ectopia lentis was found in the patients with MFS with an FBN1 mutation vs those without (P=.04). Among the 77 patients who did not meet the criteria, an FBN1 mutation was found in 9 patients (12%). No correlation was found between the severity of the phenotype and the position and nature of the FBN1 mutation. CONCLUSIONS: This study showed a significant difference in the number of FBN1 mutations between patients fulfilling and those not fulfilling the diagnostic criteria for MFS, which seems to be a good predictor of the presence of an FBN1 mutation. A comprehensive clinical evaluation is mandatory before establishing a definitive diagnosis. An FBN1 mutation analysis is helpful to identify individuals at high risk for MFS who need careful follow-up, particularly in families displaying phenotypic variability and in children.

Adolescent↗

Carrier screening for cystic fibrosis in a prenatal setting.

Maternal prenatal cystic fibrosis (CF) screening was offered from September, 1997, to April, 1999, at the Ghent University Hospital, to couples undergoing prenatal diagnosis (amniocentesis) for reasons not related to CF. Fifteen minutes were devoted to explaining CF, CF screening, and the study protocol. The purpose was to assess the short- and long-term knowledge of CF, the attitude towards carrier screening, and carriership. A total of 314 couples entered the pilot study; 13 female CF carriers were identified. None of their partners carried an identifiable mutation. Our survey results show that information about CF and CF screening can be given effectively as part of antenatal care because most couples recalled important medical and genetic issues, valued the genetic test for CF, and seemed to cope well with the results. Risk estimates and actual numbers were more difficult to process and recall. From the small number of couples in which the woman alone was found to be a carrier, there was little or no evidence of marked distress.

Adolescent↗

Association between Cys282Tyr missense mutation and haptoglobin phenotype polymorphism in patients with chronic hepatitis C.

INTRODUCTION: In patients with chronic hepatitis C infection, the haptoglobin (Hp) 1-1 phenotype is overrepresented. Data regarding the occurrence of the Cys282Tyr missense mutation in these patients are less clear. We studied the prevalence of both variables in a cohort of patients with chronic hepatitis C and looked for interaction between the two variables. MATERIALS AND METHODS: The study group consisted of 142 patients chronically infected with the hepatitis C virus. All patients were examined for the occurrence of the Cys282Tyr missense mutation, and in 132 of them the Hp phenotype was determined. The Cys282Tyr missense mutation was detected by restriction fragment length polymorphism (RFLP) using a standard polymerase chain reaction (PCR) technique and RsaI digestion. Hp phenotypes were determined using starch gel electrophoresis of haemoglobin-supplemented serum followed by peroxidase staining. RESULTS: A significant overrepresentation of the Hp 1-1 phenotype was found (36/132, 27%, P < 0.01 v. control population). This overrepresentation was observed only in the patients homozygous for the wild-type allele of the HFE gene. The Cys282Tyr allele was significantly overrepresented in hepatitis C patients (0.12 v. 0.07, P < 0.05) and principally in patients with the Hp 2-1 and 2-2 phenotypes. CONCLUSION: In patients with chronic hepatitis C infection, both the Hp 1-1 and the Cys282Tyr allele occur more frequently than in a control population. Remarkably, these genes seem to determine each other's occurrence, such that the overrepresentation of the Hp 1-1 phenotype is seen only in Cys282Tyr-negative subjects, while the overrepresentation of the Cys282Tyr allele is observed in Hp 1-1-negative subjects. Differences in immunomodulating and in oxidative stress-inducing capacities between the two genes may explain this finding.

Adult↗

Fifteen new mutations (-195C>T, L-12X, 298-2A>G, T117N, A159T, R229S, 997+2T>A, E274X, A331T, H364R, D389G, 1256delC, R433H, N461I, C472S) in the tissue-nonspecific alkaline phosphatase (TNSALP) gene in patients with hypophosphatasia.

Hypophosphatasia is a rare inherited disorder characterized by defective bone mineralization and deficiency of serum and liver/bone/kidney-type alkaline phosphatase (L/B/K ALP) activity. We report the characterization of tissue-nonspecific alkaline phosphatase (TNSALP) gene mutations in a series of 12 families affected by severe or mild hypophosphatasia. Twenty distinct mutations were found, 5 of which were previously reported. Nine of the 15 new mutations were missense mutations (T117N, A159T, R229S, A331T, H364R, D389G, R433H, N461I, and C472S). The others were 2 nonsense mutations (L-12X and E274X), one single nucleotide deletion (1256delC), 2 mutations affecting splicing (298-2A>G, 997+2T>A), and a mutation in the major transcription start site (-195C>T). Hum Mutat 15:293, 2000.

Alkaline Phosphatase↗

Refined genetic and physical mapping of BPES type II.

BPES is a genetic disorder including blepharophimosis, ptosis of the eyelids, epicanthus inversus and telecanthus. Type I is associated with female infertility, whereas type II presents without other symptoms. Both types I and II occur sporadically or are inherited as an autosomal dominant trait. We present a molecular genetic and cytogenetic study in a large four-generation Belgian family with BPES type II. Karyotype analysis on high-resolution banded chromosomes yielded normal results. Fluorescence in situ hybridization (FISH) with cosmid probes spanning 3q22-q24 revealed normal hybridization patterns. Sixteen polymorphic CA repeats encompassing region 3q13-q25 were analysed. Linkage analysis in this large four-generation family provides conclusive evidence for the presence of a BPES gene in this region. Two-point lod scores greater than 3.0 between the disease and the following markers were seen: D3S1589 (4.67), D3S1292 (3.52), D3S1290 (3.59) and D3S1549 (3.65). By FISH, D3S1290, D3S1292 and D3S1549 were assigned to chromosome 3q23 using YACs positive for these markers.

Belgium↗

Effect of halothane genotype, breed, feed withdrawal, and lairage on pork quality of belgian slaughter pigs.

A total of 434 Belgian Landrace (B) or Piétrain x B (PB) pigs, of known halothane genotype (NN, Nn, and nn), were slaughtered in a commercial abattoir. Pigs were either fed until loading or deprived of food overnight before delivery. Upon arrival at the abattoir, pigs were slaughtered after different lairage times (within 1 h after arrival, after 2 to 3 h lairage, or 4 to 5 h lairage). Meat quality traits were measured on the carcass, as well as on a piece of loin. Halothane genotype was the predominant factor determining meat quality traits related to the PSE condition (P < .001 for pH 40 min after death, internal reflectance, color L value; P < .01 for drip losses, transmission value). For these traits, nn pigs were always significantly different from Nn and NN pigs. Depending on the specific trait, Nn pigs were intermediate between NN and nn pigs, or close to NN pigs. For pH 40 min after death and drip losses, Nn and NN pigs were significantly different, whereas the difference between Nn and NN pigs was not significant for internal reflectance, color L value, and transmission value. Shear force and intramuscular fat content were apparently not related to the PSE condition and were not influenced by the halothane genotype (P > .05). Differences in meat quality between B and PB pigs and between gilts and barrows were rather unimportant compared with the effect of halothane genotype. Overnight feed withdrawal had no effect on meat quality (P > .05 for all PSE-related traits). On the other hand, holding pigs a few hours in lairage improved meat quality compared with immediate slaughtering (P < .05 for pH and temperature in the loin 40 min after death, internal reflectance, color L value, transmission value, drip losses). This effect was more pronounced in stress-susceptible pigs than in stress-resistant pigs.

Abattoirs↗

Fibrillin immunofluorescence in pseudoxanthoma elasticum.

BACKGROUND: Pseudoxanthoma elasticum (PXE) is a rare heritable connective tissue disorder manifested by skin, ocular, and cardiovascular anomalies. The basic defect is unknown; however, the microscopic findings are indicative of defects in elastic fibers. Among the components of the elastic fibers are elastin and elastin-associated microfibrils. OBJECTIVE: We assessed the fidelity of this fibrillar system in PXE with the use of antibodies to fibrillin, a major component of elastin-associated microfibrils. METHODS: Using a well-established immunofluorescence assay, we studied fibrillin deposition in dermal fibroblast cultures from 16 patients with PXE. RESULTS: Six of the 16 patients (37%) showed some abnormality of fibrillin deposition in fibroblasts derived from lesional skin. Fibroblasts from nonlesional skin displayed normal fibrillin immunofluorescence. The only sibship studied, however, was discordant for fibrillin immunostaining. CONCLUSION: Unlike the findings in Marfan syndrome, these data are not suggestive of causal fibrillin defects in PXE.

Actin Cytoskeleton↗

Genetic linkage between the collagen type VII gene COL7A1 and pretibial epidermolysis bullosa with lichenoid features.

Pretibial epidermolysis bullosa is a rare form of dominant dystrophic epidermolysis bullosa. The disease was diagnosed after considerable delay in a large Belgian family and was remarkable for its late age at onset and its misleading clinical presentation in the proband, which strongly resembled keratosis lichenoides chronica. Both recessively and dominantly inherited forms of dystrophic epidermolysis bullosa have been shown to be linked to the collagen type VII gene, COL7A1. Two-point linkage analysis with two intragenic polymorphisms (PvuII, AluI) in COL7A1 was performed. Strong genetic linkage between the disease in this family and COL7A1 was demonstrated by a lod score of 4.45 (theta = 0) for the AluI polymorphism. The observed intrafamilial variability of clinical phenotypes contradicts the presently proposed classification of dominantly inherited dystrophic epidermolysis bullosa.

Adult↗

On the variability of the Brachmann-de Lange syndrome in seven patients.

The results of the clinical and radiographic study of 7 patients support the view of a unimodal and rather narrow phenotypic spectrum in the Brachmann-de Lange syndrome (BDLS) and reject the existence of a "classic" type of patient and a "mild phenotype" without upper limb defects who survive with moderate to severe mental retardation. Similarity among all patients is greater than their phenotypic differences. Strict clinical definition of the syndrome warrants easier access to the still unknown cause, most probably a single gene mutation with autosomal dominant inheritance.

Arm↗

Pseudoxanthoma elasticum: similar autosomal recessive subtype in Belgian and Afrikaner families.

A multidisciplinary survey of the clinical and genetic characteristics of 26 Belgian and 32 Afrikaner families with biopsy-proven pseudoxanthoma elasticum (PXE) was undertaken. The major PXE phenotype emerging from this study is very similar in both patient groups and is characterized by severe ophthalmologic manifestations with variable, mild cutaneous and vascular symptoms. In the families with more than one affected relative, segregation analysis is compatible with autosomal recessive inheritance in both groups. It is suggested that the PXE phenotype of these Belgian and Afrikaner patients is distinct from the other recognized PXE subtypes. The phenotypic resemblance in both patient groups raises the question whether a similar genetic mechanism is involved.

Adult↗

Genetic counseling of a couple presenting respectively terminal transverse defects and congenital arthrogryposis.

A 29-year-old woman consulted together with her husband for a problem of congenital joint contractures. Clinical findings in the woman were characteristic of "amyoplasia congenita". In view of the severe distal limb involvement, the possibility of a distal arthrogryposis was also considered. Unexpectedly, the husband presented terminal transverse defects, mainly of the feet, suggestive of Adams-Oliver syndrome, an autosomal dominant condition with variable expression. This discovery significantly altered the counseling given to the couple, i.e. they had to be given a high recurrence risk for congenital limb malformations in their offspring and rigorous echographic monitoring of future pregnancies was advised.

Adult↗

Familial congenital esophageal atresia. Personal case report and review of the literature.

Esophageal atresia with or without tracheoesophageal fistula (EA +/- TEF) usually occurs sporadically either as an isolated malformation or in conjunction with other congenital anomalies. Seventy-six familial cases are recorded in the literature. Two personal cases are additionally reported. An overview of the 33 pedigrees with familial occurrence of EA is presented. All available data of relevance for genetic analysis are compiled in eight tables. Attention is given to possible heterogeneity between sporadic and familial and between isolated and associated EA. Guidelines for genetic counseling are presented. With exception of the cases where EA is part of a chromosomal or of a known monogenic or teratogenic syndrome, the recurrence risks fit into a multifactorial scheme.

Abnormalities, Multiple↗

Retinal detachment and HLA typing.

105 patients with retinal detachment were HLA types and divided into hyperopic, emmetropic and myopic groups. None of these different groups showed a statistically significant correlation with any of the HLA antigens. For the patient group as a whole, there was a slightly significant correlation with HLA-B8 at the corrected p level of 0.05.

HLA Antigens↗

Familial dermatoglyphic analysis in syndactyly type I.

A familial dermatoglyphic study of 25 syndactyly type I patients and 53 unaffected first-degree relatives showed a significant increase of complex fingertip patterns in the patients and in their relatives as well. An embryonic link between the formation of complex fingertip patterns and syndactyly type I is postulated. The study contributes new data on the hereditary transmission of syndactyly type I which cannot be used for individual genetic counseling. Calculation of the recurrence risk is difficult in view of the reduced penetrance of the gene.

Belgium↗