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D Lacombe

Publications and source records attributed to D Lacombe.

At least 19 recordsLinked to original sources
PubMed2001

Large-scale deletions and SMADIP1 truncating mutations in syndromic Hirschsprung disease with involvement of midline structures.

Hirschsprung disease (HSCR) is a common malformation of neural-crest-derived enteric neurons that is frequently associated with other congenital abnormalities. The SMADIP1 gene recently has been recognized as disease causing in some patients with 2q22 chromosomal rearrangement, resulting in syndromic HSCR with mental retardation, with microcephaly, and with facial dysmorphism. We screened 19 patients with HSCR and mental retardation and eventually identified large-scale SMADIP1 deletions or truncating mutations in 8 of 19 patients. These results allow further delineation of the spectrum of malformations ascribed to SMADIP1 haploinsufficiency, which includes frequent features such as hypospadias and agenesis of the corpus callosum. Thus, SMADIP1, which encodes a transcriptional corepressor of Smad target genes, may play a role not only in the patterning of neural-crest-derived cells and of CNS but also in the development of midline structures in humans.

Abnormalities, Multiple↗
PubMed2001

Identification of the gene altered in Berardinelli-Seip congenital lipodystrophy on chromosome 11q13.

Congenital generalized lipodystrophy, or Berardinelli-Seip syndrome (BSCL), is a rare autosomal recessive disease characterized by a near-absence of adipose tissue from birth or early infancy and severe insulin resistance. Other clinical and biological features include acanthosis nigricans, hyperandrogenism, muscular hypertrophy, hepatomegaly, altered glucose tolerance or diabetes mellitus, and hypertriglyceridemia. A locus (BSCL1) has been mapped to 9q34 with evidence of heterogeneity. Here, we report a genome screen of nine BSCL families from two geographical clusters (in Lebanon and Norway). We identified a new disease locus, designated BSCL2, within the 2.5-Mb interval flanked by markers D11S4076 and D11S480 on chromosome 11q13. Analysis of 20 additional families of various ethnic origins led to the identification of 11 families in which the disease cosegregates with the 11q13 locus; the remaining families provide confirmation of linkage to 9q34. Sequence analysis of genes located in the 11q13 interval disclosed mutations in a gene homologous to the murine guanine nucleotide-binding protein (G protein), gamma3-linked gene (Gng3lg) in all BSCL2-linked families. BSCL2 is most highly expressed in brain and testis and encodes a protein (which we have called seipin) of unknown function. Most of the variants are null mutations and probably result in a severe disruption of the protein. These findings are of general importance for understanding the molecular mechanisms underlying regulation of body fat distribution and insulin resistance.

Acanthosis Nigricans↗
PubMed2001

Leucodystrophy and oculocutaneous albinism in a child with an 11q14 deletion.

We report a patient with an undetermined leucodystrophy associated with type 1A oculocutaneous albinism (OCA). Type 1 OCA results from recessive mutations in the tyrosinase gene (TYR) located in 11q14.3. The patient was found by FISH to carry a deletion of at least the first exon of the TYR gene on one chromosome and a (TG) deletion at codon 244/245 on the second chromosome. The existence of the microdeletion suggested that a gene responsible for leucodystrophy was located in the vicinity of the TYR gene. A combination of a test of hemizygosity and contig mapping studies allowed us to map the gene within a 0.6 cM region flanked by microsatellite markers D11S1780 and D11S931.

Adolescent↗
PubMed2000

Case with autistic syndrome and chromosome 22q13.3 deletion detected by FISH.

Autism is a rare neurodevelopmental disorder with a strong genetic component. Co-occurrence of autism and chromosomal abnormalities is useful to localize candidate regions that may include gene(s) implicated in autism determinism. Several candidate chromosomal regions are known, but association of chromosome 22 abnormalities with autism is unusual. We report a child with autistic syndrome and a de novo 22q13.3 cryptic deletion detected by FISH. Previously described cases with 22q13.3 deletions shared characteristic developmental and speech delay, but autism was not specifically reported. This case emphasizes a new candidate region that may bear a gene involved in autism etiopathogenesis. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:839-844, 2000.

Adolescent↗
PubMed2000

Costello syndrome: report of six patients including one with an embryonal rhabdomyosarcoma.

UNLABELLED: Costello syndrome was first described in 1971. Besides papillomata, which were part of the initial description, patients tends to develop benign tumours of ectodermal origin. Aetiology is yet unknown but it is supposed to be the result of a sporadic dominant mutation. We report six patients with typical clinical findings and emphasise the importance of cardiac manifestations and the tendency to develop tumours. One patient developed an embryonal rhabdomyosarcoma, the occurrence of which has been reported twice before in patients with Costello syndrome. CONCLUSION: There might be a causal link between the development of rare tumours and this genetic disorder which may provide a new clue concerning the identification of the gene involved in Costello syndrome.

Cardiomyopathy, Hypertrophic↗
PubMed2000

Schizencephaly: clinical and imaging features in 30 infantile cases.

Schizencephaly is an uncommon structural disorder of cerebral cortical development, characterized by congenital clefts spanning the cerebral hemispheres from the pial surface to the lateral ventricles and lined by cortical gray matter. Either an antenatal environmental incident or a genetic origin could be responsible for this lesion which occurs between the third and fourth month of gestation. We report the clinical and cranial imaging features of 30 children, of whom 15 had unilateral and 15 had bilateral lesions. Their ages at the time of the first presentation ranged from 1 month to 10 years. They were thoroughly studied from clinical, epileptical, imaging and electroencephalographic (EEG) viewpoints. Five patients were investigated by cranial computed tomography (CT), eight by cranial magnetic resonance (MR) imaging, and 17 by both methods. The clinical features consisted of mild hemiparesis in 17 cases (57%), 12/17 were related to a unilateral phenotype (80% of all unilateral forms) and 5/17 to a bilateral phenotype. A tetraparesis was present in nine cases, all of which were due to a bilateral cleft. Bilateral forms were significantly associated with tetraparesis, whereas unilateral forms were associated with hemiparesis. Mental retardation was observed in 17 cases (57%), and was observed significantly more often in bilateral clefts (80%). When both hemispheres are involved, an absence of reorganization of the brain function between the two hemispheres leads to severe mental deficits, in addition to the cerebral anomaly itself. Eleven patients had seizures (seven from unilateral and three from bilateral forms). The degree of malformation was not related to the severity of epilepsy. Migration disorders, such as dysplasia or heterotopia, were observed in 30% of cases and are also important etiopathogenetic factors. The septum pellucidum was absent in 13 cases (43%), with septo-optical dysplasia in two cases. Corpus callosum dysgenesis was noted in 30% of cases. Four cases of mega cisterna magna were noted. Although familial cases and environmental factors have been previously reported, schizencephaly appears to be, in the majority of cases, sporadic.

Adolescent↗
PubMed2000

Statistical analysis of mitochondrial pathologies in childhood: identification of deficiencies using principal component analysis.

Mitochondrial pathologies are a heterogeneous group of metabolic disorders that are frequently characterized by anomalies of oxidative phosphorylation, especially in the respiratory chain. The identification of these anomalies may involve many investigations, and biochemistry is a main tool. However, considering the whole set of biochemical data, the interpretation of the results by the traditionally used statistical methods remains complex and does not always lead to an unequivocal conclusion about the presence or absence of a respiratory chain defect. This arises from three main problems: (a) the absence of an a priori-defined control population, because the determination of the control values are derived from the whole set of investigated patients, (b) the small size of the population studied, (c) the large number of variables collected, each of which creates a wide variability. To cope with these problems, the principal component analysis (PCA) has been applied to the biochemical data obtained from 35 muscle biopsies of children suspected of having a mitochondrial disease. This analysis makes it possible for each respiratory chain complex to distinguish between different subsets within the whole population (normal, deficient, and, in between, borderline subgroups of patients) and to detect the most discriminating variables. PCA of the data of all complexes together showed that mitochondrial diseases in this population were mainly caused by multiple deficits in respiratory chain complexes. This analysis allows the definition of a new subgroup of newborns, which have high respiratory chain complex activity values. Our results show that the PCA method, which simultaneously takes into account all of the concerned variables, allows the separation of patients into subgroups, which may help clinicians make their diagnoses.

Adolescent↗
PubMed2000

Oxaliplatin or paclitaxel in patients with platinum-pretreated advanced ovarian cancer: A randomized phase II study of the European Organization for Research and Treatment of Cancer Gynecology Group.

PURPOSE: This was a multicentric, open, randomized, phase II study of single-agent paclitaxel and oxaliplatin to evaluate the efficacy of oxaliplatin in a relapsing progressive ovarian cancer patient population and to analyze the safety profile and impact of both agents on quality of life, time to progression, and survival. PATIENTS AND METHODS: Eighty-six patients with platinum-pretreated advanced ovarian cancer were randomly assigned to two arms: 41 received paclitaxel at 175 mg/m(2) over 3 hours every 3 weeks, and 45 received oxaliplatin at 130 mg/m(2) over 2 hours every 3 weeks. For inclusion, patients had to have a performance status of 0 to 2 and to have received at least one and no more than two prior cisplatin- and/or carboplatin-containing chemotherapy regimens within the last 12 months. RESULTS: Seven confirmed responses were observed in each arm, for an overall response rate in the total treated population of 17% (95% confidence interval [CI], 7% to 32%) in the paclitaxel arm and 16% (95% CI, 7% to 29%) in the oxaliplatin arm. Median time to progression was 14 weeks and 12 weeks, and overall survival was 37 weeks and 42 weeks in the paclitaxel and oxaliplatin arms, respectively. Among 63 patients with a 0- to 6-month progression-free, platinum-free interval, there were five objective responses with paclitaxel in 31 patients and two objective responses with oxaliplatin in 32 patients. Nine patients (22%) in the paclitaxel arm had grade 3 or 4 neutropenia (National Cancer Institute of Canada [NCIC] Common Toxicity Criteria). Two patients (4%) experienced grade 3 thrombocytopenia in the oxaliplatin arm. Maximum grade (grade 3) NCIC neurosensory toxicity was experienced by three patients (7%) in the paclitaxel arm and by four patients (9%) in the oxaliplatin arm. CONCLUSION: Single-agent oxaliplatin at 130 mg/m(2) every 3 weeks is active with moderate toxicity in patients with cisplatin-/carboplatin-pretreated advanced ovarian cancer.

Adult↗
PubMed2000

Clinical and molecular genetic spectrum of autosomal dominant Emery-Dreifuss muscular dystrophy due to mutations of the lamin A/C gene.

Emery-Dreifuss muscular dystrophy (EDMD) is characterized by early contractures of the elbows and Achilles tendons, slowly progressive muscle wasting and weakness, and life-threatening cardiomyopathy with conduction blocks. We recently identified LMNA encoding two nuclear envelope proteins, lamins A and C, to be implicated in the autosomal dominant form of EDMD. Here, we report on the variability of the phenotype and spectrum of LMNA mutations in 53 autosomal dominant EDMD patients (36 members of 6 families and 17 sporadic cases). Twelve of the 53 patients showed cardiac involvement exclusively, although the remaining 41 all showed muscle weakness and contractures. We were able to identify a common phenotype among the patients with skeletal muscle involvement, consisting of humeroperoneal wasting and weakness, scapular winging, rigidity of the spine, and elbow and Achilles tendon contractures. The disease course was generally slow, but we observed either a milder phenotype characterized by late onset and a mild degree of weakness and contractures or a more severe phenotype with early presentation and a rapidly progressive course in a few cases. Mutation analysis identified 18 mutations in LMNA (i.e., 1 nonsense mutation, 2 deletions of a codon, and 15 missense mutations). All the mutations were distributed between exons 1 and 9 in the region of LMNA that is common to lamins A and C. LMNA mutations arose de novo in 76% of the cases; 2 of these de novo mutations were typical hot spots, and 2 others were identified in 2 unrelated cases. There was no clear correlation between the phenotype and type or localization of the mutations within the gene. Moreover, a marked inter- and intra-familial variability in the clinical expression of LMNA mutations exists, ranging from patients expressing the full clinical picture of EDMD to those characterized only by cardiac involvement, which points toward a significant role of possible modifier genes in the course of this disease. In conclusion, the high proportion of de novo mutations together with the large spectrum of both LMNA mutations and the expression of the disease should now prompt screening for LMNA in familial and sporadic cases of both EDMD and dilated cardiomyopathy associated with conduction system disease.

Adolescent↗
PubMed2000

[Cleft lip and palate. Epidemiologic analysis: report of 60 cases].

The authors reviewed 60 cases of cleft lip and palate between November 1996 and May 1998. Any family history of cleft lip and palate and associated syndromes was noted, to detect a possible mode of transmission. A family history of cleft lip and palate was reported in 14 cases (23%). Possible autosomal dominant transmission was observed in this series. A syndromic form was observed in eight cases (13%), with one case of Van der Woude's Syndrome (VWS), and another of velo-cardiofacial Syndrome (VCFS). Molecular and chromosomal studies are indicated in both cases. A Pierre Robin sequence (PRS) was found in six cases.

Cleft Lip↗