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Mutations in LGI1 have been reported in several families with autosomal dominant lateral temporal epilepsy. In a family in which three patients also experienced migraine-like episodes we found a novel three base-pair deletion (c.377_379delACA), resulting in the deletion of an asparagine residue in the second leucine-rich repeat. Functional studies showed that the mutated protein was not secreted when transfected in COS cells, consistent with a causative role in the disease.

DYT1 dystonia are one of the exceptions in human genetics with its unique and recurrent mutation (c.907delGAG). In this rare movement disorder, the mutation is associated with incomplete penetrance as well as great clinical variability, making this disease a benchmark to search for genetic modifiers. Recently, Risch et al. have demonstrated the implication of the rs1801968 SNP in disease penetrance. We attempted to replicate this result in an exhaustive DYT1 French population with no success. Our results argue that the rs1801968 H allele effect is not part of the modifiers in the French population of DYT1 patients and that others have to be identified in our population., ((c) 2008 Movement Disorder Society.)

Unlabelled: Hereditary hemorrhagic telangiectasia (HHT) is a genetic disease characterized by cutaneous, mucosal, and sometimes visceral arteriovenous malformations. Severe hepatic manifestations have been characterized in a subgroup of patients, but few data are available in previously nonscreened patients. We prospectively evaluated liver involvement and its cardiac consequences in such patients. Between 2000 and 2005, we prospectively evaluated the clinical, biological, and hepatic Doppler sonography (DS) characteristics of 102 consecutive HHT patients (mean age, 52.5 years; range, 19-88; 80.4%) with an identified genetic mutation. Patients were segregated into three different severity groups according to DS values. Factors predictive of an abnormal DS, according to predetermined criteria, and of a high cardiac index were identified by logistic and linear regression analysis, respectively. Abnormal liver biology and clinical signs of hepatic involvement were present in 35.3% and 27.5% of cases, respectively. Abnormal DS (defined as at least enlargement of the main hepatic artery) was observed in 56 (54.9%) cases, and direct or indirect signs of significant fistulas were present in 26 (25.5%) cases. Abnormal liver biology and a mutation involving the ACVRL1 gene were predictive of hepatic ultrasound (US) abnormalities. The diameter of the main hepatic artery and the presence of focal nodular hyperplasia (FNH) were predictive of a higher cardiac index., Conclusion: This large prospective series of previously nonscreened HHT patients identified a subgroup at risk of liver involvement (patients with abnormal liver biology and ACVRL1 mutations) and a subgroup with a higher cardiac index: future studies will show whether such patients would benefit from systematic DS screening and long-term cardiac surveillance.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease characterized by widespread arteriovenous malformations and caused by mutations in two major genes: ENG and ACVRL1. Two decades ago, a French epidemiological study pointed out that its prevalence was higher than previously thought and that its distribution varied greatly from one area to another, one of the highest concentrations of patients being found in the Haut-Jura mountains. Although germline mutations are usually family specific, some of them have been reported in unrelated patients, especially for ACVRL1. We performed haplotype analysis of 116 French and Italian patients carrying 13 ACVRL1 different mutations. For five of these mutations, we estimated the age of the most recent common ancestors (MRCAs) using the ESTIAGE program. Most mutations were related to both recurrent mutational events and founder effects with age estimates ranging from 100 to 550 years. The c.1112dupG mutation, which is likely to be responsible for the very high concentration of HHT patients found in the former epidemiological study, probably occurred in one inhabitant of the Haut-Jura Mountains more than three centuries ago. The p.Arg374Gln mutation occurred independently in at least two distinct geographical areas, including the area with the second highest prevalence in the epidemiological study and where the MRCA is rather recent (about 100 years ago). Partially shared haplotypes between French and Italian patients were found for three mutations. This suggests a common origin and a possible diffusion of these mutations from Italy to France.

Early onset torsion dystonia are rare movement disorders. Molecular defect is known for only a subgroup, consisting of a unique and recurrent mutation in the TOR1A gene. We undertook a nationwide census of French TOR1A-mutation carriers and the assessment of clinical associated signs. Overall, 53 index cases and 104 relatives were studied and haplotypes linked to the mutation constructed. The previously reported Ashkenazi-Jewish haplotype was found in 11 families with the remainder carrying distinct haplotypes suggesting independent mutation events. This study demonstrates the scarcity of this disease in France with estimated disease frequency of 0.13:100,000 and mutation frequency of 0.17:100,000.

Objective: To assess whether pulmonary arteriovenous malformation (PAVM) is associated with hereditary hemorrhagic telangiectasia (HHT)., Study Design: This study was a review of 12 children (sex ratio = 1) including family history, mutation analysis, and long-term follow-up., Results: Five children were under age 3 years when PAVM was diagnosed. Presentations included pulmonary symptoms (n = 8), cerebral abscess (n = 2), and transient ischemic attack (TIA) (n = 1); 1 patient was asymptomatic. Nine of the 12 children (75%) had a family history of PAVM. The diagnosis of HHT was confirmed in all cases. A mutation in ENG was found in 9 of the 10 children available for testing. No mutation in ACVRL1 was found. During long-term follow-up (mean, 16 years), the following complications occurred: TIA (n = 2), hemoptysis (n = 2), and cerebral abscess (n = 2). Nine children experienced recurrence of PAVM. The children with no recurrence were those without a family history of PAVM., Conclusions: The diagnosis of HHT should be considered in a child with an apparently isolated PAVM. Because serious complications may occur at any age, we recommend screening for PAVM and long-term follow-up in children from families with HHT, especially those with an ENG mutation.

Mental retardation affects 2 to 3% of the population and is marked by significant etiological heterogeneity, including genetic and non genetic causes. FRAXA (FMR1) trinucleotide expansion is widely searched in routine screening, but found in only about 2% of the patients tested. Mutations of the MECP2 (methyl-CpG-binding protein) gene mainly cause Rett syndrome but were also shown to be involved in mental retardation. This study aimed to estimate the frequency of MECP2 gene mutations in a large group of mentally retarded patients without FRAXA expansion. Screening by heteroduplex analysis and SSCP followed by DNA sequencing of shifted bands were performed on 613 patients, including 442 males and 171 females. Eleven sequence variants were found, including nine polymorphisms. The two others may be pathogenetic. The first one, the double nucleotide substitution c.1162_1163delinsTA leading to a premature stop codon (p.Pro388X) was found in a female patient with random X-inactivation, presenting with borderline mental impairment without any features of Rett syndrome. The second one, the c.679C>G substitution, changing a glutamine to a glutamate in the transcriptional repression functional domain (p.Gln227Glu), was found in a female patient with a moderately biased X-chromosome inactivation profile and presenting with mild intellectual delay and minor psychotic features. The low mutation rate suggests that a large-scale routine screening for MECP2 in mentally retarded subjects is not cost-effective in clinical practice. Screening may be improved by a pre-selection based on clinical features that remain to be established.

Among 353 patients with hereditary hemorrhagic telangiectasia retrospectively analyzed during the period 1985-2005, we identified 67 cases of severe infection that affected 48 patients (13.6%). Extracerebral infections accounted for 67% of all infections, and most involved Staphylococcus aureus and were associated with prolonged epistaxis. Cerebral infections accounted for 33% of all infections, were mainly due to multiple and anaerobic bacteria, and were associated with the presence of pulmonary arteriovenous malformations and a short duration of epistaxis.

Introduction: In frame deletions of exons encoding the central rod domain of dystrophin have been associated with a highly variable phenotype, including asymptomatic individuals. The lack of family history impairs accurate genetic counselling., Observation: We report on a 4-year-old child suffering from transient episodes of limping at the age of 2 and several episodes of fall since the age of 3. Clinical examination did not show muscle weakness. CPK levels were increased (1300 UI). EMG was normal. Muscle histology showed a rhabdomyolysis without features of muscular dystrophy. Immunolabelling for dystrophin, merosin and dysferlin were normal. Western blot analysis of muscular proteins showed reduced-size dystrophin bands and a slightly reduced intensity for dystrophin, alpha and gamma-sarcoglycan. Multiplex PCR of the dystrophin gene showed an in-frame deletion of exons 50-51, predicted to be associated to a Becker type of dystrophinopathy. Intragenic markers and quantitative PCR suggested maternal inheritance. This was confirmed by testing the maternal grand-parents, revealing that the asymptomatic 69-year-old grand father was a carrier. Three additional healthy males, whose ages ranged from 28 to 55 years and who were asymptomatic, also carried the mutation. The proband became spontaneously asymptomatic and cardiac echography was normal. In light of these data, genetic counselling was more reassuring and the mutation carrier maternal aunt, who was pregnant, decided to continue the pregnancy., Conclusion: This case report emphasizes the importance of family molecular analysis, especially in males from the maternal lineage, for genetic counselling of dystrophinopathies associated to atypical features or to an isolate increase of muscular enzymes level in a young boy with no positive family history.

Hereditary hemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease is a genetic disorder with autosomal dominance and variable penetrance, characterized by epistaxis, telangiectasia and visceral manifestations of the disease. The estimated minimal prevalence is 1/10,000 inhabitants. The diagnosis is established on clinical criteria, and may be further confirmed by the identification of causative mutations in either the ENG or the ACVRL1 gene coding for endoglin and ALK1, respectively. Pulmonary vascular manifestations of HHT include pulmonary arteriovenous malformations (PAVMs; especially in patients with ENG mutations) and less frequently pulmonary hypertension (especially in patients with ACVRL1 mutations). In 15-33% of patients with HHT, PAVMs consist of abnormal communications between pulmonary arteries and pulmonary veins, causing right-to-left shunting, and thus, frequently hypoxemia and dyspnea on exertion, although PAVMs may remain asymptomatic and frequently undiagnosed unless complications occur. PAVMs result in severe and frequent complications often at a young age, which may reveal the diagnosis, e.g. transient ischemic attack and cerebral stroke (10-19% of patients), systemic severe infections and abscesses (including cerebral abscess in 5-19% of patients), and rarely massive hemoptysis or hemothorax. Infections in HHT are related to the right-to-left shunting that bypasses the pulmonary capillaries and facilitates the passage of septic or aseptic emboli into the systemic and especially cerebral circulation, and potentially to minor defects in innate immunity. Treatment of PAVMs based on transcatheter coil vaso-occlusion of the feeding artery significantly decreases right-to-left shunting, hypoxemia and dyspnea on exertion, and reduces the risk of systemic complications. Long-term follow-up is warranted after transcatheter vaso-occlusion of PAVMs due to frequent recanalization of treated PAVMs and development or growth of untreated PAVMs. Patients with HHT should be informed of the risk of PAVM and potentially severe complications occurring in heretofore asymptomatic subjects. All adult patients with HHT should be proposed systematic screening for PAVM, by contrast echocardiography (preceded by anteroposterior chest radiograph) or computed tomography of the chest. Pulmonary hypertension is rare in HHT, and may be due either to systemic arteriovenous shunting in the liver increasing cardiac output or be clinically and histologically indistinguishable from idiopathic pulmonary arterial hypertension. Pulmonary hypertension is detected by systematic examination of right cardiac cavities and tricuspid regurgitation flow at echocardiography, and the diagnosis is established by right heart catheterization., (Copyright (c) 2007 S. Karger AG, Basel.)

Purpose: Hereditary hemorrhagic telangiectasia is an autosomal dominant disorder characterized by arteriovenous malformations (AVM), mostly cutaneous and mucous (telangiectases), but also involving the lungs (PAVM), liver (HAVM) and brain (CAVM). We studied the relationship between the phenotype and genotype in patients with a proven mutation in either ENG (HHT1) or ACVRL1 (HHT2)., Methods: Clinical features and their age of onset were compared between HHT1 and HHT2. The type of mutation was also analyzed. Clinical manifestations were distinguished from lesions found by screening., Results: Ninety-three HHT1 patients and 250 HHT2 patients were included. Epistaxis occurred later in HHT2, with incomplete penetrance (P<0.0001). Symptomatic PAVMs were more frequent in HHT1 (34.4 vs. 5.2%, P<0.001), as were cerebral abscesses (7.5 vs. 0.8%, P=0.002). Gastrointestinal bleeding occurred more frequently in HHT2 (16.4 vs. 6.5%, P=0.017). Symptomatic hepatic involvement was only seen in HHT2 patients. PAVMs were more frequently detected in asymptomatic HHT1 patients (54 vs. 12.8%, P<0.0001). PAVMs and HAVMs were often family clustered in HHT1 and HHT2, respectively. Truncating mutations were associated with a higher frequency of epistaxis and telangiectasis, in HHT2., Conclusion: This study shows major differences between HHT1 and HHT2 phenotypes, which should be taken into account for future clinical studies.

Study Purpose: To formulate recommendations about clinical management of liver involvement in hereditary hemorrhagic telangiectasia (HHT), using a formal consensus development process., Consensus Process: A nominal group technique was used. A list of main clinical, diagnostic and therapeutic issues about liver involvement in HHT was generated by the organizing committee. Panel members then scored their agreement with each statement; the median score, and standard deviation for each statement were determined for each of the three successive panel rounds. These consensus statements formed the basis for recommendations graded with the strength and quality of supporting evidence., Recommendation Statements: Doppler US is sufficiently accurate and suitable for first-line imaging of the liver in the general HHT population. Liver biopsy in any patient with proven or suspected HHT should be avoided. Liver involvement in HHT is generally asymptomatic; in the minority of patients where it is symptomatic, morbidity and mortality can be substantial. The prevalence of focal nodular hyperplasia is much higher in patients with liver involvement by HHT than in the general population. Invasive therapies for liver involvement by HHT (namely liver transplantation) should be considered only in patients who have failed to respond to intensive medical therapy.

Hereditary Hemorrhagic Telangiectasia (HHT) is an autosomal dominant disease characterized by arteriovenous malformations and resulting from mutations in two major genes: ENG and ACVRL1. The aim of the present study was to estimate the prevalence of the mutations of ENG and ACVRL1 in HHT, based on the largest series of patients reported so far, recruited through a national network. We previously reported the first mutation screening of both genes, in French HHT patients, using heteroduplex analysis. This previous study, bringing 60 novel mutations, provided a significant improvement to the knowledge of molecular pathology in HHT. However, 32% (n=48) of the patients with a confirmed clinical diagnosis remained without mutation. In these patients, we performed an extensive molecular analysis that included the sequencing of the whole coding sequence, the search for large rearrangements, and screening of the potential 5' regulatory regions. Additionally, due to the lack of large pedigrees suitable for linkage analysis, and since SMAD4 germline mutations have been reported in families with combined HHT and juvenile polyposis, we screened this gene and five other genes involved in the TGF-beta/BMP pathway in the patients without mutation of ENG or ACVRL1. Only a novel SMAD1 non-conservative substitution was found in one patient, changing a poorly conserved methionine to an isoleucin. Twenty-three mutations were found in ACVRL1 and 8 in ENG (including a duplication of exons 4 to 8 and deletions of exons 1 to 3 and 9 to 14). Our results, combined with our previous data, increase the mutation rate to 88% (n=119/136) in French patients with a confirmed clinical diagnosis. Our results also emphasize the higher prevalence of large insertions/deletions in ENG and the predominance of ACVRL1 over ENG mutations.

Since the description of Rett syndrome, only a handful of epidemiologic studies based only on clinical investigation have been reported. Mutations in the MECP2 gene are associated with Rett syndrome and French laboratories have organized a clinical and molecular network to investigate the incidence of Rett syndrome in France including the results of molecular investigations. The present study, based on a large cohort of 424 patients with Rett syndrome, found that the incidence of this disease with a MECP2 mutation varied between 0.43 to 0.71 per 10,000 females. The total population of females aged 4-15 years in November 2004 in France was estimated to be 4,337,627. The data presented here indicate a prevalence of Rett syndrome of 0.558 per 10,000 females aged 4-15 years in France. The incidence of Rett syndrome is in accordance with other European epidemiologic studies based on clinical examination. Given that this is a minimum incidence because complete inventory was not possible, this study of patients with Rett syndrome reinforces the fact that the great majority of patients with Rett syndrome have a MECP2 mutation.

Orofaciodigital syndromes (OFD) are a group of diseases classified according to the phenotype and the mode of inheritance. We report on a fetus presenting with some features of the OFDs but with additional global cerebral dysgenesis. Ultrasonography at 19 weeks of pregnancy disclosed hypoplasia of the cerebral hemispheres with a large intrahemispheric cyst, as well as dysmorphic facial features and brachy-syndactyly IV-V. Fetal brain MRI confirmed these features and disclosed additional morphological anomalies: Agenesis of the vermis, complete agenesis of the corpus callosum, pachygyria of the left hemisphere. Pathological examination showed a disproportionate fetus with large head and short limbs. Dysmorphic features included hypertelorism, broad nasal root, long philtrum, severe micrognathia, microstomia, cleft palate, and lobulated tongue. Radiographs showed distal malformations of the four limbs. Neuropathological examination showed a severe disturbance of the architecture of both hemispheres, more severe on the right side, with four cystic structures located between the hemispheres. Olfactory stalks, mammillary bodies, and midline structures were absent. Cerebellum and brainstem were hypoplastic. On the right hemisphere as on most part of the left one, microscopic findings displayed a complete disruption of the developing mantle with disturbance of the neuronal migration. The present fetus fulfilled the diagnosis of OFD syndrome: Dysmorphic features, cleft palate and lobulate tongue and polysyndactylies of the feet and hands. The cerebral involvement would make it closer to OFD type VI, but brain malformations were far more severe in the present case, with complex and generalized cortical dysgenesis, evoking a disturbance occurring at a very early stage of the embryogenesis., (Copyright 2006 Wiley-Liss, Inc.)

Background: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by the presence of telangiectases and arteriovenous malformations. In some families in whom a form of idiopathic pulmonary arterial hypertension cosegregated with HHT, mutations in the ACVRL1 gene were present., Purpose: We noninvasively measured the pulmonary artery systolic pressure (PASP) in a group of patients with HHT., Methods: Doppler transthoracic echocardiography and mutation analysis by direct sequencing were used., Results: We studied 68 patients (age 19-84 years, mean 50.75 + 15.11; 32 females) and PASP measurement was possible in 44 (64. 7%); in addition, 9 of them (20.5%) showed elevated values. Molecular analysis identified mutations in the ACVRL1 gene in 7 of these 9 subjects. Even on exclusion of relatives of the single case with known pulmonary hypertension, 5 of 37 patients (13.5%) still showed values higher than those of controls., Conclusion: The data indicate that elevated PASP values are a frequent and previously unrecognized complication of HHT. Because clinically significant pulmonary artery hypertension (a relevant cause of morbidity and mortality) may subsequently develop in these patients, we propose that the measurement of PASP should be included among the parameters recorded for all patients undergoing Doppler transthoracic echocardiography during routine clinical screening.

Mutations in the MECP2 (Methyl-CpG-binding protein) gene have been reported to cause Rett syndrome (RTT), an X-linked progressive encephalopathy. Recent studies have identified large gene rearrangements that escape the common PCR-based mutation screening strategy and mutations in a novel MeCP2 isoform (named MECP2B). We have collected the results of MECP2 mutational analysis concerning 424 RTT patients conducted in eight laboratories in France. In total, 121 different MECP2 mutations were identified. R168X (11.5%) is the most common of MECP2 mutations, followed by R270X (9%), R255X (8.7%), T158 M (8.3%) and R306C (6.8%). Only eight mutations had relative frequency>3%. Large and complex rearrangements not previously detected using only a PCR-based strategy represent 5.8% of MECP2 mutations. On the contrary, mutation in exon 1 appears to be rare (less than 0.5%). These data demonstrate the high allelic heterogeneity of RTT in France and suggest that routine mutation screening in MECP2 should include quantitative analysis of the MECP2 gene. This study represents an important instrument for molecular diagnosis strategy and genetic counseling in RTT families.

Introduction: X-linked adrenoleukodystrophy (ALD) is the most frequent type of leukodystrophy (1/17 000 males). The phenotypic range in male patients varies from the severe cerebral presentations in children to the milder myeloneuropathy and to isolate adrenal insufficiency. More than a half of the carrier females display clinical symptoms over the age of 40 years., Observation: Diagnosis of ALD was raised in a 40 year-old female who presented with spastic paraparesis and sphincterian dysfunction, occurring after the delivery of her first child. There was no family history of ALD. Very long-chain fatty acids (VLFCA) were assayed in her one-year-old son in order to propose appropriate hormonal and neurological survey. His dosage was abnormal and an adrenal insufficiency was subsequently found. A brain MRI will be proposed biannually when he reaches to age of for years. The proband's mother had an increased level of VLCFA, showing that she was a carrier. Family screening was extended to the proband's sisters and maternal aunt who already had children, but also to her brother, who may express a mild form of the disease later on, and to her maternal uncles who might be asymptomatic carriers. A frameshift mutation was found in the ABCD1 gene and will allow accurate carrier identification and prenatal diagnosis in the family., Conclusion: ALD diagnosis should be evoked in a woman affected by myelopathy despite the lack of family history. Such a diagnosis has severe consequences since some of the related males may carry the mutation although they do not display any symptom at time of diagnosis, and because carrier females have a risk to both have a clinical expression of the disease and give birth to an affected boy.

Non-random de novo autosomal chromosomal rearrangements have not been shown to cause exocrine or gonadal dysfunction. We report on two siblings, a brother and a sister, both with de novo chromosomal rearrangements and gonadal deficiency including premature ovarian failure. They had normal phenotypes without additional manifestations of known chromosomal breakage syndromes (except for the gonadal dysfunction) and normal alpha-fetoprotein dosage level. The association of sperm abnormalities in the brother and ovarian dysfunction in the sister suggested an increased spontaneous chromosomal instability. Since the co-occurrence of chromosomal anomalies and reproductive failures may not be coincidental, we performed repeated chromosomal analysis of peripheral blood lymphocytes prior to proposing ICSI for IVF (for the brother). In both sibs, infertility was associated with random and non-random de novo autosomal chromosomal abnormalities. We discuss the possible relationship between these unusual clinical and cytogenetic features and their potential links to ataxia-telangiectasia.

This is the first report of a fetus affected with campomelic acampomelic dysplasia presenting with increased nuchal translucency. Ultrasonography at 13 weeks of amenorrhea showed a nuchal translucency 5.6 mm thick. The karyotype performed on amniotic fluid cells was normal (46,XY). Ultrasonography at 22 weeks revealed a normal femoral length and female genitalia. A second amniocentesis was performed to confirm the karyotype and for dosage of steroid hormones. Testosterone dosage was low, corresponding to a female fetus. Ultrasonography at 32 weeks showed growth retardation of the long bones (< 3rd centile) that were not curved. A severe malformation syndrome was suspected and the pregnancy was terminated at 33 weeks. The fetus displayed macrocephaly, facial dysmorphism and female external genitalia. X ray showed straight and thickened long bones, hypoplastic scapulae and moderate platyspondyly. In view of the association of sex reversal, hypoplasia of the scapulae, and the presence of straight long bones, campomelic acampomelic dysplasia was suspected and confirmed by the finding of a SOX9 mutation. This case shows the importance of a careful echographic survey in a fetus with a nuchal translucency > 4 mm, especially if there is discordance between phenotypic and genotypic sex, since growth retardation may occur later during the pregnancy., (Copyright 2004 John Wiley and Sons, Ltd.)

Hereditary hemmorrhagic telangiectasia (HHT, or Osler-Rendu-Weber syndrome) is an autosomal dominant disease characterized by arteriovenous malformations, affecting 1 out of 10,000 individuals in France. The disease is caused by mutations of two genes: ENG and ALK1 (ACVRL1). We screened the coding sequence of ENG and ALK1 in 160 unrelated French index cases. A germline mutation was identified in 100 individuals (62.5%). A total of 36 mutations were found in ENG, including three nonsense mutations, 19 small insertions/deletions leading to a frameshift, two inframe deletions, seven missense mutations, and five intronic or splice-site mutations. Of the 36 mutations, 33 were novel mutations. A total of 64 mutations were found in ALK1, including six nonsense mutations, 28 small insertions/deletions leading to a frameshift, one inframe deletion, 27 missense mutations, and two intronic or splice-site mutations. Of the 64 mutations, 27 were novel mutations. Mutations were found in most parts of the coding sequence for both genes, except ALK1 exon 5 and ENG exons 12 to 14. Missense mutations in ALK1 were more frequent in exons 7, 8, and 10. ENG cDNA was sequenced for three intronic mutations: c.689+2T>C produced an abnormal transcript excluding exon 5, c.1103+3&#95;1103+8del activated a cryptic splice site 22 bp upstream, and c.1428G>A produced two abnormal transcripts, one including intron 11 and the other excluding exon 10. Although most of the mutations were private, some recurrent mutations in ALK1 were of particular interest. Mutation c.1112&#95;1113dupG (p.Gly371fsX391) was found in 17 unrelated individuals sharing a common haplotype, strongly suggesting a founder effect related to the concentration of patients previously reported in a specific French region (Rhône-Alpes). Three missense mutations involved the same codon: c.1231C>T (p.Arg411Trp), c.1232G>C (p.Arg411Pro), and c.1232G>A (p.Arg411Gln) were found in seven, two, and one patients, respectively. Haplotype analysis was in favor of both a founder effect and a mutation hot-spot., (Copyright 2004 Wiley-Liss, Inc.)

Thoracic aortic aneurysm and aortic dissection (TAA and AD) are an important cause of sudden death. Familial cases could account for 20% of all cases. A genetic heterogeneity with two identified genes (FBN1 and COL3A1) and three loci (3p24-25 or MFS2/TAAD2, 5q13-q14 and 11q23.2-24) has been shown previously. Study of a single family composed of 179 members with an abnormally high occurrence of TAA/AD disease. A total of 40 subjects from three generations were investigated. In addition to five cases of stroke and three cases of sudden death, there were four cases of AD and four cases of TAA in adults. In all, 11 cases of patent ductus arteriosus (PDA) were observed, two of which were associated with TAA and one with AD. Segregation analysis showed that the distribution of these vascular abnormalities was more likely compatible with a single genetic defect with an autosomal dominant pattern of inheritance. There were no clinical signs of Marfan, Elhers-Danlos vascular type or Char syndromes. Genetic linkage analysis was performed for seven genes or loci implicated in familial TAA/AD disease (COL3A1, FBN1, 3p24-25 or MFS2/TAAD2, 5q13-q14 and 11q23.2-q24), Char syndrome (TFAP2B) or autosomal recessive PDA (12q24). Using different genetic models, linkage with these seven loci was excluded. Familial TAA/AD with PDA is likely to be a particular heritable vascular disorder, with an as yet undiscovered Mendelian genetic basis.

Intercellular adhesion molecule-1 (ICAM-1) and its receptors are adhesion molecules that play a key role in the transmigration of inflammatory cells through the blood-brain barrier, one of the earliest events in multiple sclerosis (MS), which leads to demyelination in the central nervous system. To investigate the role of genes encoding ICAM-1 and its receptors, we used a strategy of genetic linkage and association in 439 case-parent MS families of French origin, well characterized according to HLA status and severity. We demonstrate that the genes encoding ICAM-1 receptors do not influence MS susceptibility or severity. ICAM-1 had a modest, but significant effect on MS genetic susceptibility, independent of HLA and disease severity. We observed a rare, and an as yet unreported, ICAM-1 gene haplotype defined by amino acids K469 and R241 that was never transmitted to patients suggesting a protective effect against MS in our population.

Several studies have recently highlighted the fact that the clinical involvement in females carrying a mutation in the dystrophin gene could be more frequent than usually thought, suggesting the need of a careful cardiac follow-up. Except for the classical chromosomal rearrangements, it was shown that a bias in the X chromosome inactivation process could be found in some affected females. We report two families illustrating different situations. The propositus of the first family, aged 32, presented with a proximal muscular weakness, increasing for three years, as well as elevated muscular enzymes in blood. Her brother suffered from classical Duchenne muscular dystrophy. Her mother was more severely affected, whereas her sister remained asymptomatic. A duplication of exons 3 to 7 of the dystrophin gene was found in all four patients. The affected carrier from the second family was a sporadic case. She has been suffering from proximal muscular weakness for six years. Muscle biopsy showed a mosaic pattern of the immunostaining using specific antidystrophin antibodies. A stop mutation was found in exon 52. Her ten year-old daughter, carrying the mutation, was asymptomatic. In both families, the inactivation profiles were in accordance with the clinical presentation. We discuss the different mechanisms that may lead to the inactivation bias in these patients, as well as the advantage and limits of using the X chromosome inactivation test as a tool for diagnosis and prognosis purpose in symptomatic carriers for dystrophinopathies.

Nijmegen breakage syndrome (NBS) is characterized by growth retardation, microcephaly, mental retardation, immunodeficiency, and predisposition to malignancies, especially B-cell lymphomas. In contrast, leukemia is rare. A 23-year-old NBS patient presented with anemia, thrombocytopenia, and hyperlymphocytosis. The diagnosis of T-cell prolymphocytic leukemia (T-PLL) was confirmed by cytological and immunological assays (TdT(-), CD2(+), CD5(+), CD3m, and CD7(+)). Biological assays also showed a hemolytic anemia and a clotting factor V decrease. The patient was first treated by methylprednisone for 3 weeks. During this period the lymphocyte count decreased. The simultaneous normalization of the hemolysis and of factor V suggested that both could be related to T-PLL. Since T-PLL is refractory to conventional therapies with a poor prognosis, an intensive chemotherapy such as 2'-deoxycoformycin with anti-CDw52 monoclonal antibodies is usually favored. In the present case, however, because of the specific context (i.e., NBS-induced immunodepression, severe hemolytic anemia, and acquired factor V deficiency), he received pentostatin weekly during 1 month and in maintenance during 6 months. At last follow-up (7 months) he showed a persistent control of the lymphocytosis with no side effect.

Fever is one of the most frequent clinical signs encountered in pathology, especially with respect to infectious diseases. It is currently thought that the role of fever on immunity is limited to activation of innate immunity; however, its relevance to activation of adaptive immunity remains unclear. Dendritic cells (DCs) that behave as sentinels of the immune system provide an important bridge between innate and adaptive immunity. To highlight the role of fever on adaptive immunity, we exposed murine bone marrow-derived lipopolysaccharide (LPS)- or live bacteria-maturing DCs over a 3-h period to 37 degrees C or to fever-like thermal conditions (39 degrees C or 40 degrees C). At these three temperatures, we measured the kinetics of cytokine production and the ability of DCs to induce an allogeneic mixed lymphocyte reaction. Our results show that short exposure of DCs to temperatures of 39 degrees C or 40 degrees C differentially increased the secretion of interleukin (IL)-12p70 and decreased the secretion of IL-10 and tumor necrosis factor alpha by maturing DCs. These fever-like conditions induced a regulation of cytokine production at the single-cell level. In addition, short-term exposed LPS-maturing DCs to 39 degrees C induced a stronger reaction with allogeneic CD4(+) T cells than maturing DCs incubated at 37 degrees C. These results provide evidence that temperature regulates cytokine secretion and DC functions, both of which are of particular importance in bacterial diseases.

Background: FRAXE is a second locus associated with X chromosome fragility. Similar to FRAXA, the common mutation is a GCC expansion located in the 5' untranslated region, leading to the hypermethylation of the region and to the subsequent inactivation of specific genes (FMR1 and FMR2, respectively). Unlike FRAXA, FRAXE has a rare occurrence and is less currently studied in routine analyses. The phenotype associated with FRAXE is usually considered as mild or moderate mental retardation, with incomplete penetrance. However, phenotype/genotype relations have been less characterized., Objective: We report a French family with three members affected with mental retardation, including a female suffering from West syndrome, and two mentally retarded males., Methods: After exclusion of the FRAXA expansion by Southern blot analysis, we performed a karyotype using folate-thymidine-deficient medium and a southern blot to search for FRAXE expansion., Results: All three mentally retarded patients had a number of repeats over 800 GCC and expressed more than 20% of fragile sites in their leukocytes. Another carrier female with a full expansion had a subnormal mental impairment., Conclusions: Clinical features and both the cytogenetic and molecular findings seem to correlate in this family. We discuss the bias encountered when studying such families and some of the mechanisms that may explain part of the clinical variability.

We studied 15 patients, from 10 families, who presented with severe spastic paralysis with an infantile onset and an ascending progression. Spastic paraplegia began during the first 2 years of life and extended to upper limbs within the next few years. During the first decade of life, the disease progressed to tetraplegia, anarthria, dysphagia, and slow eye movements. Overall, the disease was compatible with long survival. Signs of lower motor-neuron involvement were never observed, whereas motor-evoked potentials and magnetic resonance imaging demonstrated a primitive, pure degeneration of the upper motor neurons. Genotyping and linkage analyses demonstrated that this infantile-onset ascending hereditary spastic paralysis (IAHSP) is allelic to the condition previously reported as juvenile amyotrophic lateral sclerosis at the ALS2 locus on chromosome 2q33-35 (LOD score 6.66 at recombination fraction 0). We analyzed ALS2, recently found mutated in consanguineous Arabic families presenting either an ALS2 phenotype or juvenile-onset primary lateral sclerosis (JPLS), as a candidate gene. In 4 of the 10 families, we found abnormalities: three deletions and one splice-site mutation. All the mutations lead to a truncated alsin protein. In one case, the mutation affected both the short and the long alsin transcript. In the six remaining families, absence of cDNA ALS2 mutations suggests either mutations in regulatory ALS2 regions or genetic heterogeneity, as already reported in JPLS. Alsin mutations are responsible for a primitive, retrograde degeneration of the upper motor neurons of the pyramidal tracts, leading to a clinical continuum from infantile (IAHSP) to juvenile forms with (ALS2) or without (JPLS) lower motor-neuron involvement. Further analyses will determine whether other hereditary disorders with primitive involvement of the central motor pathways, as pure forms of spastic paraplegia, could be due to alsin dysfunction.

Background: Hereditary factors have been reported in 5-10% of cases with exocrine pancreatic cancer and recent data support a role for BRCA2., Aims: We have studied the prevalence of germline BRCA2 mutations in two groups of patients with exocrine pancreatic cancer from an unselected series in Spain: group A included 24 cases showing familial aggregation of cancer and group B included 54 age, sex, and hospital matched cases without such evidence., Methods: Information was obtained by interview of patients and was validated by a telephone interview with a structured questionnaire. In patients from group A, >80% of the coding sequence of BRCA2 was analysed; in patients from group B, the regions in which germline BRCA2 mutations have been described to be associated with pancreatic cancer were screened., Results: Telephone interviews led to reclassification of 7/54 cases (13%). Familial aggregation of cancer was found in 24/165 cases (14.5%); six patients had a first degree relative with pancreatic cancer (3.6%) and nine patients had relatives with breast cancer. Germline BRCA2 mutations were not identified in any patient from group A (0/23). Among group B cases, one germline variant (T5868G>Asn1880Lys) was found in a 59 year old male without a family history of cancer. The 6174delT mutation was not found in any of the 71 cases analysed., Conclusions: The overall prevalence of BRCA2 mutations among patients with pancreatic cancer in Spain is low and the 6174delT mutation appears to be very infrequent. Our data do not support screening patients with cancer of the pancreas for germline BRCA2 mutations to identify relatives at high risk of developing this tumour.

GENERAL DATA: The clinical manifestations and neuropathological signs of multiple sclerosis have been recognized for more than one hundred years, but the cause remains unknown., Epidemiology: Multiple sclerosis is not evenly distributed throughout the world. There is an important north-south gradient in the northern hemisphere and inversely in the southern hemisphere; multiple sclerosis is more frequent in the higher altitudes. For a given latitude, there is a difference by ethnic origin. These observations indicate that multiple sclerosis is a multifactorial condition determined by both genetic and environmental factors., Strategies of Genetic Studies: Progress in our knowledge of the human genome and statistical analysis techniques have made it possible to search for genetic factors in multiple sclerosis using two complementary approaches. The first is by anonymous screening and the second is to search for a candidate gene. The HLA locus is the only one with an identified predisposing effect for multiple sclerosis. It only accounts for 10 to 20% of the genetic predisposition for multiple sclerosis and many factors remain to be discovered.

Andermann syndrome or Agenesis of the Corpus Callosum with Polyneuropathy (MIM 218000) is an autosomal recessive disease almost exclusively found in Québec. Only few cases have been reported in other populations. The locus for Andermann syndrome was assigned to chromosome 15q13-q15 in French Canadian families. We performed a haplotype analysis with two markers of this chromosomal region in an Algerian consanguineous family with two affected sibs. The children were homozygous for both markers, suggesting genetic homogeneity in Andermann syndrome.

Background: Recent advances in the field of molecular genetics have provided useful tools for the diagnosis of neuromuscular disorders. Genetic counselling for many of these conditions may, however, be fraught with difficulties., Case Report: The patient, two paternal uncles and a paternal aunt presented with clinical and electromyographic evidence of type III spinal muscular atrophy despite an autosomal dominant-like pedigree. The diagnosis was confirmed by genetic testing for the SMN deletion. As the proband's mother was pregnant at the time of presentation of the affected child, a prenatal diagnostic test was performed. The deletion was not found in the DNA extracted from the trophoblast and the pregnancy proceeded to full term, and a normal child. At the same time, a first cousin of the proband was found to have a clinically similar condition. He had not the SMN deletion. He presented with electrophysiological and pathological features of limb-girdle muscular dystrophy. Genetic testing revealed a homozygote del T521 mutation of the gama-sarcoglycan gene., Conclusion: To provide accurate genetic counselling, it is essential to get precise data on family background and diagnostic confirmation for each affected relative to avoid missing the possibility, albeit rare, of several neuromuscular disorders within a family.

Unlabelled: HNPP occurs rarely but not exceptionally during childhood., Case Report: José M., seven years old, presented an isolated radial nerve palsy of progressive onset with no other clinical feature. There was no family history of neurological disorder. The electromyogram (EMG) showed a 'mosaic-like' pattern of extended sensitive and motor alterations, with diminished conduction velocities and amplitudes and increased distal latencies. HNPP was considered through the association of an isolated radial nerve palsy with an asymptomatic polyneuropathy, and was confirmed by molecular biology., Conclusion: HNPP is generally considered on clinical features, heredity and EMG findings. Molecular biology confirms the diagnosis in most of the cases, even in apparently sporadic patients, and is of great interest in atypical cases.