Intracranial dissemination of primary spinal cord anaplastic oligodendroglioma.

We report the first case of a 22-year-old man, with a previously neurosurgically treated intramedullary anaplastic oligodendroglioma (World Health Organization grade III), who developed 19 months later two histologically proven intracranial metastases. We support a hypothesis whereby the anaplastic parts of tumors have spread along the spinal cord and brainstem via the cerebrospinal fluid pathways, a process that could be promoted by surgical manipulation, although the relative contribution of the two factors remains speculative.

[Myasthenia gravis and pregnancy: clinical course and management of delivery and the postpartum phase]. / Myasthénie auto-immune et grossesse: évolution clinique, accouchement et post-partum.

OBJECTIVES: To study influences of pregnancy on the time-course of myasthenia gravis (MG) and of MG on pregnancy, delivery, postpartum and newborn. METHODS: We retrospectively collected data from 100 women affected with MG, hospitalized between 1994 and 2003 in departments of Neurology of Lille University Hospital. RESULTS: Eighteen patients had a total of 36 pregnancies, occurring 7.2 years on average after MG onset. MG exacerbation occurred in 7 patients (26 percent) during pregnancy and in 4 (14.8 percent) during postpartum. One patient died of acute respiratory failure during postpartum. Delay between the onset of MG and pregnancy was the only variable significantly associated with MG exacerbation: 5.8 years when exacerbation and 9.5 years when no exacerbation (p=0.03). Seven miscarriages, two therapeutic abortions and no death at birth were reported. Levels of anti-acetylcholine receptor antibodies were abnormal in 3 of 27 newborns (11 percent), but only one (3.7 percent) developed seronegative transient neonatal myasthenia gravis. DISCUSSION: During pregnancy, the clinical course of MG is variable but exacerbations were associated with a shorter delay between MG diagnosis and pregnancy. The risk of transient neonatal myasthenia gravis is relatively small but exists even when the parturient has stable MG without elevated levels of anti-acetylcholine receptor antibodies. CONCLUSION: Our study confirms pregnancy is more difficult to manage at the beginning of MG. Given the unpredictable course of MG during pregnancy, we recommend women affected with MG to begin a pregnancy when the disease is stable.

A dinucleotide repeat polymorphism at the poly(ADP-ribose) polymerase gene is not associated with predisposition to type 1 diabetes in French Caucasians.

The poly (ADP-ribose) polymerase (PARP) is a nuclear enzyme that detects and binds DNA strand breaks. Excessive PARP activation leads to the death of mice islet beta-cells by depleting cellular energy reserves. On the other hand, PARP-mutant mice are resistant to streptozotocine-induced diabetes, and in the non-obese diabetic (NOD) mouse model, treatment with nicotinamide, a PARP inhibitor, protects islet cells against cytotoxic actions in vitro and results in a decreased incidence of type 1 diabetes. PARP gene in human is located within a recently identified type 1 diabetes-susceptibility region on chromosome 1q41-42, and contains a polymorphic CA dinucleotide repeat in the promoter region. To consider the putative involvement of PARP polymorphism in predisposition to type 1 diabetes, we performed genotyping for the various alleles of the CA dinucleotide repeat in 158 unrelated French Caucasian patients with type 1 diabetes and 193 ethnically-matched healthy controls. We found no significant difference of PARP alleles distribution between patients and controls, even after stratification of the patients according to HLA class II genotype or to age at disease onset. Our results suggest that this PARP polymorphism does not influence susceptibility to type 1 diabetes in French Caucasians.

Poly(ADP-ribose) polymerase alleles in French Caucasians are associated neither with lupus nor with primary antiphospholipid syndrome. GRAID Research Group. Group for Research on Auto-Immune Disorders.

OBJECTIVE: To investigate the putative involvement of poly(ADP-ribose) polymerase (PARP) alleles in systemic lupus erythematosus (SLE) and primary antiphospholipid syndrome (APS). METHODS: This study of French Caucasians included 171 unrelated patients with SLE, 88 unrelated patients with primary APS, and 193 ethnically matched healthy controls. The SLE group comprised 89 patients with sporadic SLE and 82 patients with familial SLE. Patients' and controls' DNA were genotyped for the various alleles of a polymorphic CA dinucleotide repeat located within the promoter region of PARP. RESULTS: No statistically significant difference was observed for the distribution of PARP alleles between the healthy control group and each patient group or the pooled SLE patient group. CONCLUSION: The study findings strongly suggest that these alleles do not influence susceptibility to SLE or primary APS in French Caucasians.

TCR alpha beta gene usage for myelin basic protein recognition in healthy monozygous twins.

The pathogenic role of myelin basic protein (MBP)-specific T lymphocytes in multiple sclerosis (MS) has been suggested by the encephalitogenicity of MBP-specific T cells in experimental allergic encephalomyelitis (EAE). In humans, extensive analysis of TCRs involved in MBP recognition has led to conflicting results, varying from an intra- and/or interindividual restriction to high diversity in TCRAV/TCRBV gene usage. We previously established MBP-specific T cell lines (TCLs) from healthy monozygous twins and characterized their fine epitope specificity. In this study, we report on the TCR alpha beta gene usage of 52 of these MBP TCLs that are specific for epitopes recognized by both co-twins within the same pair. High overall diversity in the TCR alpha and TCR beta genes used for recognition of this self-Ag, MBP, was observed. Variable genes belonging to 19 different TCRAV and 16 different TCRBV subfamilies are expressed by the 52 TCLs herein studied. In co-twins, TCLs utilized genes belonging to common TCRAV and/or TCRBV gene subfamilies in 7 of 13 instances of shared epitope recognition. Statistical analysis of intrapair concordance for TCR gene usage for the recognition of a given peptide did not show any significant deviation from values that would be anticipated in the absence of genetic background effect.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, genetic homogeneity, and mapping of the locus within a 2-cM interval.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently identified autosomal dominant cerebral arteriopathy characterized by the recurrence of subcortical infarcts leading to dementia. A genetic linkage analysis conducted in two large families recently allowed us to map the affected gene on chromosome 19 in a 12-cM interval bracketed by D19S221 and D19S215. In the present study, these first 2 families and 13 additional ones, including a total of 199 potentially informative meiosis, have been genotyped with eight polymorphic markers located between D19S221 and D19S215. All families were linked to chromosome 19. The highest combined lod score (Zmax = 37.24 at theta = .01) was obtained with marker D19S841, a new CAn microsatellite marker that we isolated from chromosome 19 cosmids. The recombinant events observed within these families were used to refine the genetic mapping of CADASIL within a 2-cM interval that is now bracketed by D19S226 and D19S199 on 19p13.1. These data strongly suggest the genetic homogeneity of this recently identified condition and establish the value of its clinical and neuroimaging diagnostic criteria. Besides their importance for the ongoing positional cloning of the CADASIL gene, these data help to refine the genetic mapping of CADASIL relative to familial hemiplegic migraine and hereditary paroxysmal cerebellar ataxia, conditions that we both mapped within the same chromosome 19 region.

Genetic heterogeneity of familial hemiplegic migraine.

Familial hemiplegic migraine (FHM) is an autosomal dominant variety of migraine with aura. We previously mapped a gene responsible for this disorder to the short arm of chromosome 19, within a 30-cM interval bracketed by D19S216 and D19S215. Linkage analysis conducted on two large pedigrees did not show any evidence of heterogeneity, despite their clinical differences due to the presence, in one family, of cerebellar ataxia and nystagmus. Herein we report linkage data on seven additional FHM families including another one with cerebellar ataxia. Analysis was conducted with a set of seven markers spanning the D19S216-D19S215 interval. Two-point and multipoint lod score analyses as well as HOMOG testing provided strong evidence for genetic heterogeneity. Strong evidence of linkage was obtained in two families and of absence of linkage in four families. The posterior probability of being of the linked type was > .95 in the first two families and < .01 in four other ones. It was not possible to draw any firm conclusion for the last family. Thus, within the nine families so far tested, four were linked, including those with associated cerebellar ataxia. We could not find any clinical difference between the pure FHM families regardless of whether they were linked. In addition to the demonstration of genetic heterogeneity of FHM, this study also allowed us to establish that the most likely location of the gene was within an interval of 12 cM between D19S413 and D19S226.

The gene for spondyloepiphyseal dysplasia (SEDL) maps to Xp22 between DXS16 and DXS92.

Previous linkage studies in X-linked spondyloepiphyseal dysplasia (SEDL) placed the gene in the region Xp22.2-p22.1 by linkage to DXS41. Here we have extended our earlier studies by analyzing 15 families with 13 markers from the Xp22 region. Pairwise linkage analysis revealed significant linkage of the SEDL to 8 markers from the Xp22.2-Xp22.1 region. Maximum lod scores were obtained with DXS207, tau max = 9.16 at theta max = 0.021 with confidence limits of 0.00-0.09, and DXS197, tau max = 7.98 at theta max = 0.00 with confidence limits of 0.00-0.06. The study of one recombinant in family 4 indicated that DXS 41 is more likely proximal to DXS92 than distal. Multipoint linkage results and analysis of recombination events indicated that the mutation responsible for SEDL is located in Xp22 between DXS 16 and DXS 92.

A gene for Usher syndrome type I (USH1A) maps to chromosome 14q.

Usher syndrome (US) is an autosomal recessive disease characterized by congenital hearing impairment and retinitis pigmentosa. It is the most frequent cause of deaf-blindness in adults and accounts for 3 to 6% of deaf children. Here, we report the genetic mapping of a gene for US type I (USH1A), the most severe form of the disease, to the long arm of chromosome 14, by linkage to probe MLJ14 at the D14S13 locus in 10 families of Western France ancestry (Z = 4.13 at theta = 0). Among them, 8 families originated from a small area of the Poitou-Charentes region (Z = 3.78 at theta = 0), suggesting that a founder effect could be involved. However, since not all US type I families were found to be linked to this locus, the present study provides evidence for genetic heterogeneity of this condition (heterogeneity versus homogeneity test HOMOG, P < 0.05; heterogeneity versus no linkage, P < 0.01).

The gene for X-linked hydrocephalus maps to Xq28, distal to DXS52.

We report the study of five independent X-linked hydrocephalus (HSAS1) families with polymorphic DNA markers of the Xq28 region. A total of 58 individuals, including 7 living affected males and 22 obligate carriers, have been studied. Maximum lod score was 7.21 at theta = 2.40% for DXS52 (St14-1). A single recombination event was observed between this marker and the HSAS1 locus. Other markers studied were DXS296 (Z = 2.02 at theta = 2.5%), DXS304 (Z = 4.37 at theta = 7.8%), DXS74 (Z = 3.50 at theta = 0%), DXS15 (Z = 1.96 at theta = 5.7%), DXS134 (Z = 3.31 at theta = 0%), and F8C (Z = 5.79 at theta = 0%). These data confirm the localization of the HSAS1 gene to Xq28 and provide evidence for genetic homogeneity of this syndrome. In addition, examination of two obligate recombinant meioses along with multipoint linkage analysis supports the distal localization of the HSAS1 locus with respect to the DXS52 cluster. These observations are of potential interest for future studies aimed at HSAS1 gene characterization.

Phenotype-genotype correlations in X linked retinitis pigmentosa.

Retinitis pigmentosa (RP) represents a group of clinically heterogeneous retinal degenerations in which all modes of inheritance have been described. We have previously found two different clinical profiles in X linked RP as a function of age and mode of onset. The first clinical form has very early onset with severe myopia. The second form starts later with night blindness with mild myopia or none. At least two genes have been identified in X linked forms, namely RP2 (linked to DXS7, DXS255, and DXS14) and RP3 (linked to DXS84 and OTC) on the short arm of the X chromosome. In order to contribute to phenotype-genotype correlations in X linked RP, we tested the hypothesis that the two clinical profiles could be accounted for by the two different gene loci. The present study provides evidence for linkage of the clinical form with early myopia as the onset symptom with the RP2 gene (pairwise linkage to DXS255: Z = 3.13 at theta = 0), while the clinical form with later night blindness as the onset symptom is linked to the RP3 gene (pairwise linkage to OTC: Z = 4.16 at theta = 0).