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1/22. Benign idiopathic partial epilepsy and brain lesion.

    A 14-year-old girl had severe head trauma from a dog bite at the age of 9 days. This resulted in extensive brain damage, tetraplegia, mental retardation, and epilepsy. The seizures were of rolandic type, and the EEG showed multifocal sharp waves. The course was benign. The initial diagnosis of a pure symptomatic epilepsy was revised after demonstrating typical benign focal sharp waves in the EEG of the healthy sister. Thus a phenocopy of a benign partial epilepsy by the brain lesion could be excluded with sufficient certainty. This observation allows the conclusion that the genetic disposition underlying the sharp-wave trait characteristic of benign partial epilepsies can be involved also in the pathogenesis of seemingly pure symptomatic epilepsies. EEG studies on siblings of such patients are needed to exclude possible phenocopies.
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keywords = wave
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2/22. Inherited susceptibility to aminoglycoside ototoxicity: genetic heterogeneity and clinical implications.

    PURPOSE: Aminoglycoside-induced ototoxicity appears to have a genetic susceptibility in some individuals, and the A1555G mutation in the mitochondrial 12S ribosomal rna gene has been shown to be responsible for this susceptibility in all familial cases. An Italian family with 5 family members who became deaf after aminoglycoside exposure presented to us, and molecular analysis excluded the A1555G mutation. The purpose of this study is to identify the molecular basis for the aminoglycoside susceptibility in this family. patients AND methods: Two sisters and three of their children developed severe to profound high-frequency hearing loss after aminoglycoside exposure. dna was extracted from the blood of these individuals and their unaffected relatives, and analyzed for mitochondrial dna mutations. The region around nucleotide 961 was also cloned and individual clones were sequenced. RESULTS: Sequencing of the 12S ribosomal rna gene revealed a thymidine deletion at position 961, with a complex pattern of sequence around this mutation. Sequencing of individual clones around the 961 mutation demonstrated a varying number of inserted cytosines in different mitochondrial molecules. CONCLUSION: This family establishes the nucleotide 961 thymidine deletion associated with a varying number of inserted cytosines in the mitochondrial 12S ribosomal rna gene as the second pathogenic mutation that can predispose to aminoglycoside ototoxicity. It demonstrates the clinical relevance of taking a family history before administering aminoglycosides to any patient. In addition, it would be desirable for sporadic patients with aminoglycoside-induced hearing loss to be screened with molecular tests for the presence of the 1555 and 961 mutations. Such screening could significantly decrease the prevalence of aminoglycoside-induced hearing loss.
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ranking = 1.0920265833904
keywords = frequency
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3/22. Low frequency of the ccr5delta32 HIV-resistance allele in mainland china: identification of the first case of ccr5delta32 mutation in the Chinese population.

    A 32-bp deletion on the CCR5 gene (ccr5delta32) confers resistance to hiv-1 infection. This deletion is common in Caucasians, but rare in Asians. Since the frequency of the ccr5delta32 allele of Chinese in mainland china has been unknown we investigated the ccr5delta32 mutation in a cohort of 407 Chinese people in this area. A 225-bp fragment of CCR5 encompassing the 32-bp region was analysed by PCR, hybridization and sequencing. Only 1 out of 407 subjects was heterozygous for ccr5delta32 and no homozygotes were detected. The frequency of ccr5delta32 in this cohort is thus 0.00123, i.e. much lower than that of Caucasians. The ccr5delta32 heterozygote is a healthy young man. To our knowledge this is the first ccr5delta32 mutant found in Chinese people. The results indicate that ccr5delta32 does exist in Chinese people, but at very low frequency. This suggests that ccr5delta32 is not a significant factor for the genetic resistance to hiv-1 in Chinese people.
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ranking = 7.6441860837327
keywords = frequency
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4/22. Mutations of the XLRS1 gene cause abnormalities of photoreceptor as well as inner retinal responses of the ERG.

    Intensity-series rod and cone ERGs were recorded in 19 patients with XLRS and 26 control eyes. All patients were examined by one ophthalmologist and diagnosed on the basis of fundus appearance and evidence of the disease in other males in the same family. Mutations in the XLRS1 gene have been identified in 15 of the patients. Dark-adapted ERGs were significantly different from controls for all test conditions and for both a-wave and b-wave responses. Abnormalities were detectable in all patients but there was considerable variation in the severity of abnormality. One third of the patients had the dark-adapted 'negative-wave' response typically associated with inner retinal disorder, but about one third showed only mild depression of the b-wave while the remainder had abnormally low a-waves in addition to depressed b-waves. light-adapted responses were also affected and both a-wave and b-wave responses differed significantly from controls, but the 'negative-wave' response was not seen in any patient. The severity of the ERG abnormality did not correlate with the classification of fundus appearance or patient age suggesting that retinal function is relatively stable throughout life. The severity of ERG abnormalities did not correlate with the type of mutation and responses could differ between affected males within the same family. These results indicate considerable heterogeneity of ERG response without clinical, age or genetic correlate. The abnormal a-wave responses indicate that photoreceptor as well as inner retinal layer function may be affected in XLRS, at least in some patients.
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ranking = 3.3333333333333
keywords = wave
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5/22. bartonella henselae associated uveitis and HLA-B27.

    AIM: To investigate the frequency of HLA-B27 in patients with presumed bartonella henselae associated uveitis and to describe the clinical characteristics of HLA-B27 positive patients with uveitis and presumed ocular bartonellosis (POB). methods: The diagnosis of POB was considered in 19 patients with unexplained uveitis (except for the HLA-B27 association) and high positive IgG (titre >/=1:900) and/or IgM (titre >/=1:250) antibodies against B henselae. In addition to B henselae serology and HLA-B27 typing, all patients underwent an extensive standard diagnostic screening procedure for uveitis and in all cases the results were within the normal limits. The control group consisted of 25 consecutive patients with panuveitis and negative B henselae serology. RESULTS: HLA-B27 was positive in six of the 19 patients (32%) with POB in contrast to the 4% frequency of HLA-B27 in the control group (p=0.03) and 8% prevalence of HLA-B27 in the Dutch population (p=0.003). At the time of positive Bartonella serological testing five of six HLA-B27 positive patients with POB had severe posterior segment involvement with papillitis, macular oedema, and vitreitis. The duration of intraocular inflammatory activity was more than 6 months in five HLA-B27 positive patients. Although four of the six HLA-B27 positive patients had previous recurrent attacks of acute anterior uveitis, the clinical presentation at the time of positive Bartonella serology differed, as illustrated by the involvement of the posterior segment and chronic course of the ocular disease. CONCLUSIONS: The frequency of HLA-B27 in patients with uveitis and serological characteristics of acute infection with B henselae is higher than in the general Dutch population. The findings of this study also suggest a relation between infection with Bartonella species and HLA-B27.
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ranking = 3.2760797501711
keywords = frequency
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6/22. A second case of inv(4)pat with both recombinants in the offspring: rec dup(4q) in a girl with wolf-hirschhorn syndrome and rec dup(4p).

    In a girl presenting with features of wolf-hirschhorn syndrome, cytogenetic and molecular cytogenetic analysis revealed a rearranged chromosome 4 with monosomy of the distal bands 4pter-->4p16.2 and trisomy of the distal bands 4q35.1-->4qter [rec dup(4q)] due to a large, paternal pericentric inversion. In the following two pregnancies, prenatal diagnosis showed the same imbalance in one fetus and a reverse segmental imbalance [rec dup(4p)] in the other. We discuss the recombination risk of the given inversion with respect to the size of the inverted segment and the viability of the recombinants. The high frequency of recombinants in this family and others suggests a high recurrence risk in similar cases with large pericentric inversions comprising almost entire chromosomes.
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ranking = 16.22985162468
keywords = high frequency, frequency
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7/22. Is the P25L a "real" VHL mutation?

    BACKGROUND: The von Hippel-Lindau (VHL) gene has two translational initiation sites separated by 53 codons. Both proteins have been detected in cells and have equivalent activity. A mutation in the first 53 codons of the open reading frame has no effect on the structure of the smaller protein. As expected, the vast majority of VHL mutations are downstream of the second initiation site and alter both proteins. However, several candidate mutations have been found in the first 53 codons, including a substitution of leucine for proline at position 25 (P25L) of the larger protein. methods AND RESULTS: dna sequence analysis showed two VHL gene mutations, P25L and P86R, in an individual with a clinical diagnosis of VHL disease. Both mutations have been reported previously. P25L alters only the upstream protein, whereas P86R alters both VHL proteins. Based on the positions of the mutations, P86R is more likely to be pathogenically significant than the P25L mutation. A survey of anonymized DNAs for P25L, using allele-specific PCR, revealed that it is a variant with an allele frequency of approximately 0.5%. CONCLUSION: P25L is a rare variant of the VHL gene and cannot be considered a cause of VHL disease. However, this work does not prove that P25L is entirely innocuous.
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ranking = 1.0920265833904
keywords = frequency
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8/22. A genome screen of a large bipolar affective disorder pedigree supports evidence for a susceptibility locus on chromosome 13q.

    Bipolar affective disorder is a severe mood disorder that afflicts approximately 1% of the population worldwide. Twin and adoption studies have indicated that genetic factors contribute to the disorder and while many chromosomal regions have been implicated, no susceptibility genes have been identified. In this present study, we undertook a 10 cM genome screen using 400 microsatellite markers in a large multigenerational bipolar pedigree consisting of 40 individuals, including six affecteds. We found strongest evidence for linkage to chromosome 13q14. A maximum NPL score of 4.09 (P = 0.008) was obtained between markers D13S1272 and D13S153 using GENEHUNTER. A maximum two-point lod score of 2.91 (theta = 0.0) was found for marker D13S153 and a maximum three-point lod score of 3.0 was obtained between markers D13S291 and D13S153 under a recessive model with 90% maximum age-specific penetrance and including bipolar I and unipolar individuals as affected. Several other markers in the region, D13S175, D13S218, D13S263, and D13S156 had two-point LOD scores greater than 1.5. These results meet the criteria for evidence of suggestive linkage. Haplotype analysis enabled us to narrow the likely disease region to a 6 cM region between markers D13S1272 and D13S1319, which contains the serotonin 2A receptor candidate gene. Two single nucleotide polymorphisms were identified in this gene but we did not detect any significant differences in allele frequency in a case-control sample. The region on chromosome 13q14-32 has previously been implicated in other bipolar and schizophrenia cohorts. Our results provide further support for the existence of a susceptibility locus on chromosome 13q14.
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ranking = 1.0920265833904
keywords = frequency
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9/22. Genetic predispositions for the presence of cryoglobulinemia and serum autoantibodies in Chinese patients with chronic hepatitis c.

    Chronic hepatitis c virus (HCV) infection may induce immunological disorders in the host such as the presence of cryoglobulinemia or serum autoantibodies. The pathogenesis of these phenomena remains unclear but may reflect the host's genetic predispositions. The aim of this study was to evaluate the association between these immunological manifestations and human leukocyte antigen (HLA) expression in Chinese patients with chronic hepatitis c. The presence of serum cryoglobulin and autoantibodies (antinuclear antibody, antismooth muscle antibody, antimitochondrial antibody, antiliver-kidney-microsomal antibody) was determined in 122 Chinese patients with chronic hepatitis c. HLA class I and class II antigens were measured by microlymphocytotoxicity assay or by dna typing in 122 chronic hepatitis c patients and 228 healthy controls. Of the 122 patients with chronic hepatitis c, 52 (43%) had cryoglobulinemia and 48 (39%) had serum autoantibodies. A significant difference in HLA frequency was noted for DR3, which was found in 36.5% of patients with cryoglobulinemia compared with 8.6% of patients without cryoglobulinemia and 11.3% of healthy controls. A significant difference in HLA frequency was also noted for DR4, which was found in 45.8% of patients with serum autoantibodies compared with 17.6% of patients without serum autoantibodies and 19% of healthy controls. Our results suggest the existence of HLA-linked susceptibility genes (DR3 or DR4) for the development of cryoglobulinemia or serum autoantibodies in Chinese patients with chronic hepatitis c.
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ranking = 2.1840531667808
keywords = frequency
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10/22. crohn disease in patients with familial mediterranean fever.

    crohn disease and familial mediterranean fever (FMF) are inflammatory diseases characterized by abdominal pain and fever. The concurrence of the 2 diseases (FMF-CD) may pose a challenge to diagnosis and treatment. We undertook the present study to determine the prevalence of crohn disease in FMF and to characterize FMF-CD patients clinically and genetically. Using a computerized search, the patients of our FMF clinic were screened for a concomitant diagnosis of crohn disease. patients and their medical records were thoroughly examined, and their dna was genotyped for mutations in the MEFV gene. control groups of ethnically and sex-matched patients suffering from each of the diseases alone, either crohn disease or FMF, were used for comparison. We identified 7 patients with concomitant crohn disease and FMF, which is more than the expected prevalence in the general population (p = 0.03). crohn disease presented at a significantly later age in the FMF-CD group (40.6 /- 10.0 yr versus 26.2 /- 11.4 yr; p < 0.004). Disease severity and other characteristics of crohn disease were comparable to the crohn disease control group. Contrary to the FMF control group patients, FMF in FMF-CD patients was characterized by a higher attack frequency (p < 0.05) and increased prevalence of amyloidosis (p < 0.02). The overall severity score was similar in both groups. In conclusion, crohn disease appears to be more prevalent in FMF and presents later than in patients without FMF. FMF in this group of patients shows a higher attack frequency and is more often complicated by amyloidosis.
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ranking = 2.1840531667808
keywords = frequency
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