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C Francannet

Publications and source records attributed to C Francannet.

At least 19 recordsLinked to original sources
PubMed2001

Denaturing high-performance liquid chromatography (DHPLC)-based prenatal diagnosis for tuberous sclerosis.

Tuberous sclerosis (TSC) is a frequent autosomal-dominant condition (affecting 1 in 6000 individuals) caused by various mutations in either the hamartin (TSC1) or the tuberin gene (TSC2). This allelic and non-allelic heterogeneity makes genetic counseling and prenatal diagnosis difficult, especially as a significant proportion of TSC cases are due to de novo mutations. For this reason the identification of the disease causing mutation is mandatory for accurate counseling, yet current mutation detection methods such as single-strand conformation polymorphism (SSCP) or denaturing gradient gel electrophoresis (DGGE) are labor intensive with limited detection efficiency. Denaturing high-performance liquid chromatography (DHPLC) is a high-throughput, semi-automated mutation detection system with a reported mutation detection rate close to 100% for PCR fragments of up to 800 bp. We used a recently described DHPLC assay allowing the efficient detection of mutations in TSC1 to analyze the DNA extracted from a chorion villus sample in order to perform a prenatal diagnosis for TSC. The fetus was found not to have inherited the deleterious mutation and the DHPLC diagnosis was confirmed by haplotype analysis. This represents the first DHPLC-based prenatal diagnosis of a genetic disease.

Chorionic Villi↗
PubMed2001

X-linked myopathy with excessive autophagy: a clinicopathological study of five new families.

In 1988, Kalimo et al. (Ann Neurol 23 (1988) 258)described a new type of X-linked myopathy in a Finnish family. The clinical course was characterized by slow progression of muscle weakness without loss of ambulation in childhood and no evidence of cardiac, respiratory, or central nervous system involvement. Muscle fibers were not necrotic and showed excessive autophagic activity and exocytosis of the phagocytosed material. These authors proposed the name X-linked myopathy with excessive autophagy. Subsequently, only one French family has been reported with similar clinical and histopathological data. We report here five new families with a total of eight affected boys with the same clinical and histopathological features as reported in the original families. Histopathological findings of an asymptomatic mother are also reported. Vacuolar changes in muscle fibers result both from invaginations of the sarcolemma along with a variable component of basal lamina and from an autophagic process. The complement C5b-9 membrane attack complex associated with MHC class 1 antigen and calcium deposits is involved in muscle fiber damage. Among the X-linked myopathies, the identification of this new type is of great interest because of its favorable prognosis and unique morphological findings.

Adolescent↗
PubMed2001

TP63 gene mutation in ADULT syndrome.

TP63 gene mutations have recently been shown to be disease causing in EEC and SHFM. Two other overlapping syndromes with ectrodactyly as a major feature, have been mapped to chromosome 3q27 close by the TP63 locus, namely the LMS and ADULT syndromes. Here, we report on a missense TP63 gene mutation in an isolated ADULT syndrome case. This finding widens the spectrum of abnormalities to be ascribed to TP63 gene in human and emphasise on the variable roles of the different Tp63 isotypes.

Abnormalities, Multiple↗
PubMed2001

An infant with Down syndrome and retinoblastoma. A possible non-fortuitous association.

AIM: To evaluate the association between Down syndrome and retinoblastoma. METHOD: Presentation of a case report and review of the literature. RESULTS: A retinoblastoma was observed in a 10-month-old boy with Down syndrome. A review of the literature yielded 14 other cases, suggesting a possible excess of retinoblastoma in Down syndrome, as previously proposed by two epidemiological studies. The possible roles of external physical agents and hyperplastic and dysplastic lesions of the retina in subjects with Down syndrome is discussed. CONCLUSION: A positive association between Down syndrome and retinoblastoma is possible. An epidemiological study on this subject is needed to better ascertain this potential link.

Child↗
PubMed2001

Genotype-phenotype correlation in hereditary multiple exostoses.

Hereditary multiple exostoses (HME) is a genetically heterogeneous autosomal dominant disorder characterised by the development of bony protuberances mainly located on the long bones. Three HME loci have been mapped to chromosomes 8q24 (EXT1), 11p11-13 (EXT2), and 19p (EXT3). The EXT1 and EXT2 genes encode glycosyltransferases involved in biosynthesis of heparan sulphate proteoglycans. Here we report on a clinical survey and mutation analysis of 42 HME French families and show that EXT1 and EXT2 accounted for more than 90% of HME cases in our series. Among them, 27/42 cases were accounted for by EXT1 (64%, four nonsense, 19 frameshift, three missense, and one splice site mutations) and 9/42 cases were accounted for by EXT2 (21%, four nonsense, two frameshift, two missense, and one splice site mutation). Overall, 31/36 mutations were expected to cause loss of protein function (86%). The most severe forms of the disease and malignant transformation of exostoses to chondrosarcomas were associated with EXT1 mutations. These findings provide the first genotype-phenotype correlation in HME and will, it is hoped, facilitate the clinical management of these patients.

Age of Onset↗
PubMed1999

Facial anomalies in D-2-hydroxyglutaric aciduria.

D-2-hydroxyglutaric aciduria is a rare autosomal recessive organic aciduria with variable clinical expression. The biochemical defect is still unknown, and genetic heterogeneity has been suggested. Here, we report on facial anomalies in two unrelated cases of D-2-hydroxyglutaric aciduria presenting with epileptic encephalopathy. In a review, we found that minor facial anomalies have been mentioned in three patients. A flat face with a broad nasal bridge and external ear anomalies were present in our patients and in reported cases. We suggest giving consideration to D-2-hydroxyglutaric aciduria as a cause of minor facial anomalies in epileptic encephalopathy of unknown origin.

Amino Acid Metabolism, Inborn Errors↗
PubMed1998

X-linked mental retardation with isolated growth hormone deficiency is mapped to Xq22-Xq27.2 in one family.

X-linked mental retardation (XLMR) includes distinct entities in which mental deficiency is either associated with specific abnormalities (syndromal) or not (nonsyndromal). We report on the clinical, neuropsychological, and laboratory findings and linkage analysis in one family with XLMR and isolated growth hormone deficiency (IGHD). Mental retardation was associated in 3 males and 5 females with short stature, microcephaly, and particular facial traits, i.e., high curved forehead, midface hypoplasia, and concave nasal bridge with nasal end of normal size and broad traits. Significant lod scores (Zmax >2) at a recombination fraction of theta = 0 were detected for 6 marker loci between DXS178 (Xq22.1) and DXS292 (Xq27.2). This mapping region overlaps that of XLMR with IGHD, recently reported by Hamel et al. [1996: Am J Med Genet 64:35-41] (Xq24-q27.3), and that of agammaglobulinemia with IGHD (Xq21.33-q22.2). This observation may confirm the suspicion of a gene involved in growth hormone regulation being localized in Xq.

Adult↗
PubMed1997

Nance-Horan syndrome: linkage analysis in 4 families refines localization in Xp22.31-p22.13 region.

Nance-Horan syndrome (NHS) is an X-linked disease characterized by severe congenital cataract with microcornea, distinctive dental findings, evocative facial features and mental impairment in some cases. Previous linkage studies have placed the NHS gene in a large region from DXS143 (Xp22.31) to DXS451 (Xp22.13). To refine this localization further, we have performed linkage analysis in four families. As the maximum expected Lod score is reached in each family for several markers in the Xp22.31-p22.13 region and linkage to the rest of the X chromosome can be excluded, our study shows that NHS is a genetically homogeneous condition. An overall maximum two-point Lod score of 9.36 (theta = 0.00) is obtained with two closely linked markers taken together. DXS207 and DXS1053 in Xp22.2. Recombinant haplotypes indicate that the NHS gene lies between DXS85 and DXS1226. Multipoint analysis yield a maximum Lod score of 9.45 with the support interval spanning a 15-cM region that includes DXS16 and DXS1229/365. The deletion map of the Xp22.3-Xp21.3 region suggests that the phenotypic variability of NHS is not related to gross rearrangement of sequences of varying size but rather to allelic mutations in a single gene, presumably located proximal to DXS16 and distal to DXS1226. Comparison with the map position of the mouse Xcat mutation supports the location of the NHS gene between the GRPR and PDHA1 genes in Xp22.2.

Abnormalities, Multiple↗
PubMed1996

[Epidemiological study of intestinal atresias: central-eastern France Registry 1976-1992].

OBJECTIVE: Our purpose was to describe the epidemiology of small intestinal atresia. STUDY DESIGN: We used data collected by the Central-East France Congenital Malformations Registry from 1976 through 1992 to evaluate the prevalence of different types of intestinal atresia in liveborn and stillborn infants and to study some demographic and clinical features such as sex ratio, multiple births, gestational age, birth weight, maternal age, maternal disease, associated malformations. RESULTS: Through surveillance of more than 1.5 million births, we identified 344 liveborn and 14 stillborn infants with intestinal atresia (1A). The prevalence of 1A was 2.25 per 10,000 livebirths. Fifty percent of the liveborn infants had duodenal atresia, 36% had jejunoileal atresia, 7% had colic atresia, 3% had intestinal duplication and 5% had multiple atresia. The twinning rate was 4.4% which is significantly higher than in the non malformed population. Gestational age was less than 37 weeks in 35.4% of the cases. Birth weight was less than 2,500 g in 52% of the cases. For those two variables we observed significant differences among the different types of malformations. Study of 1A rates by maternal age showed an increased risk below the age of 20 (p < 10(-5)). We didn't find significant differences compared to the population for ovulation induction and maternal diabetes. Study of associated malformations demonstrated significant differences in rates and types of associated malformations in the different groups of 1A which suggests heterogenous embryological mechanisms. CONCLUSION: These findings confirm the literature data for most of the epidemiological characteristics. Only the association of an increased risk in the teenage mothers group was not previously described. This finding has to be confirmed by others studies.

Abortion, Therapeutic↗
PubMed1994

LADD syndrome in five members of a three-generation family and prenatal diagnosis.

We describe five members of a three generation family with lacrimo-auriculo-dento-digital (LADD) syndrome. The circumstances in which the diagnosis was reached and the details of the case reports underline the great variability of expression of this syndrome and show that caution should be taken in genetic counselling. Prenatal ultrasound should be offered to families at risk so that severe forms of the syndrome, in which termination of pregnancy can be considered, are early detected.

Abnormalities, Multiple↗
PubMed1993

The epidemiology of three serious cardiac defects. A joint study between five centres.

The paper reports a joint study made by five member programs of the International Clearinghouse for Birth Defects Monitoring Systems. Three specific heart malformations were studied, hypoplastic left heart syndrome (HLHS), transposition of the great vessels (TGV), tetralogy of Fallot, and some epidemiological characteristics were analyzed. The prevalence at birth was estimated to be 2.0, 2.9, and 2.2 per 10,000 births, respectively. No time trend in the prevalence at birth was observed for any one of the three malformations in the total study population. When only isolated defects were considered (infants without major non-cardiac malformations), all three cardiac anomalies showed an increased rate in infants with low birth weight, short gestational duration and probably twinning. A preponderance for males was observed for each defect but was strongest among infants with tetralogy of Fallot (sex ratio 2.5 for Fallot, 1.4 to 1.5 for the other conditions). There were also differences between the three cardiac defects with respect to percentage of low birth weight, preterm births, and rate and type of associated extracardiac malformations. This paper stresses the advantage of pooling data from different registries in studies of uncommon specific malformations and infrequent characteristics.

Adult↗
PubMed1989

[Diagnosis of deficiency in cofactor of phenylalanine hydroxylase: a metabolic emergency].

We report on two cases of children suffering from biopterin synthetase deficiency. Both were treated with the same treatment schedule with biopterin and neurotransmitters: 6-hydroxytryptophan and dihydrophenylalanine (DOPA). The only difference between the two cases is the time of diagnosis and therefore of treatment. The child who was treated early has a normal neurologic development. The other one has been treated since he was 7 months old and is mentally deficient (DQ = 0.60). This older child also suffers from dystonia probably secondary to Levodopa treatment. The authors emphasize the uncertainty of these patient's evolution owing to complications of the disease itself or those due to prolonged treatment by neurotransmitters.

5-Hydroxytryptophan↗
PubMed1989

[Renal agenesis and the Fraser syndrome: 4 observations].

The authors report on 4 cases of Fraser syndrome in 2 Turkish families. Both families are consanguinous. In 3 cases there is a bilateral renal agenesis, a feature which is not usually regarded as a main one. Actually the survey of the literature reveals that renal anomalies are not infrequent in this syndrome, even though the cryptophtalmos would be lacking. A five year study of the malformations Registry of the Rhone-Alpes-Auvergne-Jura area shows that the association between renal agenesis and syndactyly (with or without the eye abnormalities) is quite rare. Such an association leads to the diagnosis of Fraser Syndrome even when cryptophtalmos is absent, and requires to look for minor ENT or ophthalmic symptoms by a careful post mortem examination.

Abnormalities, Multiple↗
PubMed1988

[Registries of malformations in the Rhône-Alps/Auvergne region. Value and limits of monitoring teratogenesis. 11 years' experience (1976-1986)].

The authors describe a population-based birth defects registry, started in 1976. The system surveys about 85,000 births per year, occurring in 140 maternity units and representing more than ten per cent of all the births in France. Monitoring first covered the Rhône-Alpes region, then was extended to the Auvergne region in 1983 and to the Jura district in 1985. The method of investigation was "multi-source", because any doctor in the zone covered was in a position to notify a malformation to the registry. (497 obstetricians, pediatricians, pediatric surgeons, fetopathologists, geneticists and cytogeneticists). Malformations were coded with a specific terminal elaborated in the registry (1,600 items). The mothers' exposures to drugs during the first trimester of pregnancy were coded by trade names. The registry is a full member of the International Clearinghouse for Birth Defects Monitoring Systems, an international organisation now including in this group 25 regional or national birth defects registries and covering more than 3 million births per year. The 1986 results of monitoring birth defects in the described registry are given as examples. Within the eleven years (1976-86), 15,000 cases of malformations were registered, and two clusters have been detected and followed-up: femoral aplasia/hypoplasia in 1980-81 and oesophageal atresia in 1984. No cause was found for these "epidemics". The strong association between in utero exposure to valproic acid with spina bifida is the main result of the activities of the registry since its creation.

Abnormalities, Multiple↗
PubMed1987

[Congenital stenosis of the aqueduct of Sylvius transmitted in an autosomal recessive mode (5 cases in 2 families)].

The authors report 5 cases of congenital hydrocephalus due to isolated stenosis of the aqueduct of Sylvius. In the first three cases (2 brothers and 1 sister) ventriculograms showed apparent obstruction of the aqueduct. A valve shunting was necessary at 1 month of age in cases 1 and 2, at 3 years of age in case 3. In cases 4 and 5 (1 brother and 1 sister) ultrasonic prenatal diagnosis showed ventriculomegaly and pregnancies were interrupted respectively at 31 and 28 weeks of gestational age. The pedigree of the families suggests that the inheritance of this abnormality is autosomal recessive. Such an inheritance is very unusual and confirms the difficulty of genetic counseling facing the first occurrence of hydrocephalus with stenosis of the aqueduct of Sylvius in a family. The prenatal diagnosis is based on fetal ultrasonic examination and may be obtained late in the pregnancy leading to therapeutic and ethical tricky decisions.

Abortion, Therapeutic↗