| 1. |
- Ponjavic, Vesna, et al.
(författare)
-
Alterations in electroretinograms and retinal morphology in rabbits treated with vigabatrin
- 2004
-
Ingår i: Documenta Ophthalmologica. - 1573-2622. ; 108:2, s. 125-133
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To determine whether long-term treatment with the anti-epileptic drug vigabatrin causes damage to rabbit retina.METHODS: Five rabbits were treated continuously with a daily dose of vigabatrin solution per orally during a period of 1-8 months. Two rabbits receiving water were used as controls. Repeated full-field electroretinograms (every two weeks) were assessed during this period. Vigabatrin serum concentration was repeatedly measured for securing successful drug administration. After termination of treatment the rabbits were sacrificed and the morphology of the sectioned retina was studied.RESULTS: In all rabbits treated with vigabatrin the serum analyses repeatedly demonstrated elevated drug concentration. Full-field electroretinograms demonstrated normal rod function in all treated rabbits, but reduced cone function in two of the five treated rabbits verified by 30Hz flicker stimulation. Morphologic studies of the sectioned retina demonstrated GFAP immunoactivity of the glial cells localized in the retinal periphery in all five treated rabbits, one of which had staining also in the centrally localized glial cells. The treated rabbits also demonstrated a weaker GAD staining in the IPL and less positive amacrine cells, compared to the controls. Only two treated rabbits had normal GABA staining while three had an enhanced GABA immunoreactivity and undistinguishable fibers in the IPL. In three out of five treated rabbits the Müller cells were short, stubby and fragmented, with swollen endfeet.CONCLUSION: This study demonstrates changes in histopathology caused by vigabatrin in an animal model, which has not been reported previously. We have found that vigabatrin orally administrated to rabbits does not affect rod function but may reduce cone function in the full-field electroretinogram, which is similar to the previously reported vigabatrin effect on the human ERG. The results indicate that vigabatrin may damage or influence, at least one cell type in the rabbit retina.
|
|
| 2. |
- Acar, C, et al.
(författare)
-
Mutation screening of patients with Leber congenital amaurosis or the enhanced S-cone syndrome reveals a lack of sequence variations in the NRL gene
- 2003
-
Ingår i: Molecular Vision. - 1090-0535. ; 9:3-4, s. 14-17
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To determine if mutations in the retinal transcription factor gene NRL are associated with retinopathies other than autosomal dominant retinitis pigmentosa (adRP). Methods: Genomic DNA was isolated from blood samples obtained from 50 patients with Leber Congenital Amaurosis (LCA), 17 patients with the Enhanced S-Cone Syndrome (ESCS), and a patient with an atypical retinal degeneration that causes photoreceptor rosettes with blue cone opsin. The 5' upstream region (putative promoter), untranslated exon 1, coding exons 2 and 3, and exon-intron boundaries of the NRL gene were analyzed by direct sequencing of the PCR-amplified products. Results: Complete sequencing of the NRL gene in DNA samples from this cohort of patients revealed only one nucleotide change. The C->G transversion at nucleotide 711 of NRL exon 3 was detected in one LCA patient; however, this change did not alter the amino acid (L237L). Conclusions: No potential disease causing mutation was identified in the NRL gene in patients with LCA, ESCS, or the atypical retinal degeneration. Together with previous studies, our results demonstrate that mutations in the NRL gene are not a major cause of retinopathy. To date, only missense changes have been reported in adRP patients, and sequence variations are rare. It is possible that the loss of NRL function in humans is associated with a more complex clinical phenotype due to its expression in pineal gland in addition to rod photoreceptors.
|
|
| 3. |
- Andréasson, Sven, et al.
(författare)
-
Behandling av alkohol- och narkotikaproblem : En evidensbaserad kunskapssammanställning
- 2001
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Utvärderingens syfteMissbruk och beroende av alkohol är ett av de största folkhälsoproblemen. Narkotikamissbruk är mindre vanligt men har stora medicinska konsekvenser för de berörda. De sociala och juridiska aspekterna är betydande. En kritisk genomgång av litteraturen vad avser behandling av abstinens, protraherad abstinens, behandling i syfte att förhindra återfall, psykologiska och sociala behandlingar för att minska återfallsrisken, behandlingsprogram och institutionsvårdens roll, samt behandling av missbruk under graviditet. Dessutom en granskning av mini-intervention i primärvård och annan vård vars syfte är att minska konsumtionen hos högkonsumenter av alkohol. Nyligen gjorda meta-analyser inom området värderas och särskild vikt fästs vid interventioner som finns eller lätt kan introduceras i den svenska vårdorganisationen. Behandlingsprogram för patienter med samtidig annan psykisk störning värderas.Så kallat lågdosberoende av bensodiazepiner och andra lugnande medel eller sömnmedel behandlas inte. Inte heller belyses effekten av behandlingar vars primära mål är kroppsliga komplikationer av missbruket, och inte heller granskas metoder att minska tillgänglighet.TillvägagångssättStrukturerad översikt, kostnadsanalyser.Insamling av primärdataSystematisk sökning i relevanta databaser, litteraturlistor i påträffade studier samt i aktuella monografier. Ingen bakre tidsbegränsning och sökning i databaser till och med februari 1999.Utgångspunkt för urval av dataHuvudsakligen randomiserade, kontrollerade, dubbelblinda studier, samt metaanalyser som baseras på sådana studier. Vad gäller långtidsförlopp och ekonomiska analyser även kohortstudier och andra naturalistiska studier.Genomgång av publikationenSamtliga studier värderas med hjälp av en i gruppen utarbetad, och med övriga psykiatriprojekt gemensam, kvalitetsmall. Alla centrala studier läses av minst två i gruppen.Färdiga manuskript värderas av styrelse, expertgrupp samt externa granskare.
|
|
| 4. |
- Andréasson, Sten, et al.
(författare)
-
Clinical studies of X-linked retinitis pigmentosa in three Swedish families with newly identified mutations in the RP2 and RPGR-ORF15 genes
- 2003
-
Ingår i: Ophthalmic Genetics. - : Swets & Zeitlinger Publishers. - 1381-6810 .- 1744-5094. ; 24:4, s. 215-223
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To describe new disease-causing RP2 and RPGR-ORF15 mutations and their corresponding clinical phenotypes in Swedish families with X-linked retinitis pigmentosa (XLRP) and to establish genotype-phenotype correlations by studying the clinical spectrum of disease in families with a known molecular defect. Methods: Seventeen unrelated families with RP and an apparent X-linked pattern of disease inheritance were identified from the Swedish RP registry and screened for mutations in the RP2 and RPGR (for the RP3 disease) genes. These families had been previously screened for the RPGR exons 1-19, and disease-causing mutations were identified in four of them. In the remaining 13 families, we sequenced the RP2 gene and the newly discovered RPGR-ORF exon. Detailed clinical evaluations were then obtained from individuals in the three families with identified mutations. Results: Mutations in RP2 and RPGR-ORF15 were identified in three of the 13 families. Clinical evaluations of affected males and carrier females demonstrated varying degrees of retinal dysfunction and visual handicap, with early onset and severe disease in the families with mutations in the ORF15 exon of the RPGR gene. Conclusions: A total of seven mutations in the RP2 and RPGR genes have been discovered so far in Swedish XLRP families. All affected individuals express a severe form of retinal degeneration with visual handicap early in life, although the degree of retinal dysfunction varies both in hemizygous male patients and in heterozygous carrier females. Retinal disease phenotypes in patients with mutations in the RPGR-ORF15 were more severe than in patients with mutations in RP2 or other regions of the RPGR.
|
|
| 5. |
- Berglund, Mats, et al.
(författare)
-
Treatment of alcohol abuse: an evidence-based review.
- 2003
-
Ingår i: Alcoholism: Clinical and Experimental Research. - 0145-6008. ; 27:10, s. 1645-1656
-
Tidskriftsartikel (refereegranskat)abstract
- This article represents the proceedings of a symposium at the 2002 annual meeting of the Research Society on Alcoholism in San Francisco, CA, organized and cochaired by Mats Berglund and Sten Thelander. The presentations were (1) Preventive interventions against hazardous consumption of alcohol, by Mikko Salaspuro; (2) Treatment of alcohol withdrawal, by Johan Franck; (3) Psychosocial treatment for alcohol problems, by Sven Andréasson and Agneta Öjehagen; and (4) Pharmacological treatment of alcohol dependence, by Mats Berglund.
|
|
| 6. |
- Eksandh, Louise, et al.
(författare)
-
Different clinical expressions in two families with Stargardt's macular dystrophy (STGD1)
- 2001
-
Ingår i: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907. ; 79:5, s. 524-530
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To describe the clinical expressions, with emphasis on electrophysiological examinations, in two Swedish families with Stargardt's macular dystrophy (STGD1). Methods. Two pairs of siblings with STGD1, for whom diagnosis had been confirmed by genetic linkage to the ABCA4 gene region, were examined regarding visual acuity, kinetic perimetry, fundus photography, full-field ERG and multifocal ERG (MERG). Possible disease-causing mutations were screened for by DNA sequencing of selected regions of the ABCA4 gene. Results. All STGD1 patients, had visual acuity 0.07-0.1. The two families presented different fundus appearances, MERGs and implicit times on. 30 Hz flicker white light full-field ERGs. Genetic analysis revealed one unique sequence variation in exon 19 of the ABCA4 gene, in one allele from the patients of one of the families. This point mutation causes the amino acid substitution T972N in the ABCR protein. Conclusion. Two pairs of siblings with STGD1 presented two different expressions of the disease regarding the distribution of the retinal dysfunction. One possible molecular explanation to the different clinical expressions may be the T972N substitution present in the ABCR protein in one of the STGD1 families investigated.
|
|
| 7. |
- Eksandh, Louise, et al.
(författare)
-
Full-field ERG in patients with Batten/Spielmeyer-Vogt disease caused by mutations in the CLN3 gene.
- 2000
-
Ingår i: Ophthalmic genetics. - 1381-6810. ; 21:2, s. 69-77
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To investigate, using full-field ERG, the retinal function in patients with Batten/Spielmeyer-Vogt disease caused by mutations in the CLN(3) gene. METHODS: Batten disease status of five patients was confirmed by the presence of vacuolated lymphocytes in peripheral blood and the identification of mutations in the Batten disease gene (CLN(3)). Visual acuity, fundus appearance, and full-field ERG were examined in all patients (age 4-19 years). The examination was repeated in one patient after 16 months. RESULTS: Three unrelated patients were homozygous for the most common mutation in CLN(3), the 1.02 kb deletion; two patients (sisters) were heterozygous for the 1.02 kb deletion and an as yet unidentified mutation in the CLN(3) gene. Full-field ERG recordings in all five patients demonstrated no rod responses and only small remaining cone responses, which could be detected with 30 Hz-flicker stimulation. Re-examination of a six-year-old girl after 16 months revealed a fast progression of the retinal degeneration. CONCLUSION: Full-field ERG recordings in Batten disease patients, both homozygous and heterozygous for the 1.02 kb deletion in the CLN( 3) gene, confirm retinal degeneration to be severe, widespread, and with a rapid progression early in the disease course. The onset of visual failure may be delayed when compared to the classic disease course, particularly in patients who are not homozygous for the most common CLN(3) mutation, a 1.02 kb deletion. In that case, the disease progression in terms of other symptoms may also be further delayed.
|
|
| 8. |
|
|
| 9. |
- Gränse, Lotta, et al.
(författare)
-
Electrophysiologic findings in two young patients with Bothnia dystrophy and a mutation in the RLBP1 gene
- 2001
-
Ingår i: Ophthalmic Genetics. - : Swets & Zeitlinger Publishers. - 1744-5094 .- 1381-6810. ; 22:2, s. 97-105
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To characterize the clinical phenotype, with emphasis on electrophysiology, of two children with suspected Bothnia dystrophy. Methods: Two unrelated affected patients, 10 and 11 years old, were studied. Ophthalmological examination included testing of visual acuity, fundus inspection and fundus photography, kinetic perimetry, full-field electroretinogram (ERG), and multifocal ERG. The presence of a mutation in exon 7 of the RLBP1 gene was investigated by DNA sequencing. Results: Both patients were homozygous for the Arg234Trp-causing mutation in the RLBP1 gene, but the resulting disease phenotype appeared to vary somewhat between them. Visual acuity was moderately reduced in one patient and normal in the other. Fundus inspection at this age revealed no pathology in either patient and there were no signs of retinitis punctata albescens, which has been described previously as a frequent clinical feature of Bothnia dystrophy. The result of kinetic perimetry was normal. The final rod threshold was moderately elevated. Full-field ERG demonstrated the uncommon combination of absent rod response and normal cone response after 40 minutes of dark adaptation. However, after prolonged dark adaptation (20-24 h), both the rod response and the dark adaptation threshold became normal. Multifocal ERG was performed in one of the patients (the one with normal visual acuity and normal fundus appearance) and showed a reduced cone response in the central region of the tested area. There was no improvement of the multifocal ERG result after 20-24 h of dark adaptation. Conclusion: Patients with mutations in the RLBP1 gene (Arg234Trp) may have a normal fundus appearance early in the disease course. Multifocal ERG can be used for the objective documentation of the disturbed macular function, especially when the patient's visual acuity and fundus appearance are normal. The rod response is absent in the electroretinogram; however, after prolonged dark adaptation (20-24 hours), the rods recover completely. The central cones do not seem to recover.
|
|
| 10. |
- Gränse, Lotta, et al.
(författare)
-
Electrophysiology and ocular blood flow in a family with dominant optic nerve atrophy and a mutation in the OPA1 gene
- 2003
-
Ingår i: Ophthalmic Genetics. - : Swets & Zeitlinger Publishers. - 1744-5094 .- 1381-6810. ; 24:4, s. 233-245
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To characterize the clinical phenotype, with emphasis on electrophysiology and blood flow measurements, of a family with dominant optic nerve atrophy and an identified mutation in the OPA1 gene. METHODS: Seven family members were examined. Ophthalmological evaluation included testing of visual acuity, ophthalmolscopy, kinetic perimetry, color vision testing, full-field electroretinography (ERG), multifocal electroretinography (MERG), and multifocal visual evoked potential (MVEP). Retrobulbar arterial blood flow and retinal capillary perfusion was measured in three patients using scanning laser Doppler flowmetry (SLDF) and color Doppler imaging techniques. PCR-SSCP and DNA sequencing determined the presence of a mutation in exon 18 of the OPA1 gene. RESULTS: The clinical characteristics varied considerably in the family. The ERG and the MERG demonstrated normal retinal function, while the MVEP was abnormal in all examined patients. Retinal and optic nerve head capillary perfusion was significantly decreased in the three patients examined with SLDF. Retrobulbar blood flow velocities were significantly decreased in the central retinal and ophthalmic arteries. In all seven examined subjects, a microdeletion (1756-1767del(12 bp)) in the OPA1 gene was identified. CONCLUSION: Patients with a mutation in the OPA1 gene have a very variable phenotype. MVEP and blood flow measurements are two new objective methods for an easier detection of this specific genetic optic nerve atrophy.
|
|
| 11. |
|
|
| 12. |
|
|
| 13. |
- Hirsch, Jan-Mikael, et al.
(författare)
-
A clinical evaluation of the Zygoma fixture: one year of follow-up at 16 clinics.
- 2004
-
Ingår i: Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. - : Elsevier BV. - 0278-2391 .- 1531-5053. ; 62:9 Suppl 2, s. 22-9
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To evaluate treatment outcome with Zygoma fixtures (Nobel Biocare, Göteborg, Sweden) with regard to fixture survival, patient satisfaction, and function of prosthesis replacement. MATERIALS AND METHODS: The treatment outcome of 76 patients treated with 145 Zygoma fixtures at 16 centers was evaluated. Patient's and dentist's evaluations of the functional and aesthetic outcome of the treatment were assessed at delivery of prosthesis and at the 1-year follow-up visit. At the 1-year follow-up visit, the status of the peri-implant mucosa around the abutments and the amount of plaque were registered. RESULTS: Sixty-six of the 76 patients, with 124 Zygoma fixtures supporting the prosthetic restorations, were evaluated at the 1-year follow-up. The overall survival rate for the Zygoma fixtures was 97.9% after 1-year of follow-up. Eighty percent of the patients were fully satisfied with both aesthetic and functional outcome at the time of prosthetic insertion and at the 1-year follow-up. All reported data from the dentists, with the exception of one restoration with several abutment screw loosenings, scored from acceptable to excellent for the aesthetic and functional outcome of the treatment. The status of peri-implant mucosa was recorded as normal in approximately 60% of the sites. Plaque, when present, was more often detected on the palatal surfaces compared with the buccal surfaces. CONCLUSION: This 1-year follow-up of Zygoma fixtures has shown good results with an acceptable number of minor complications and a majority of satisfied patients.
|
|
| 14. |
- Jacobi, Felix K, et al.
(författare)
-
Phenotypic expression of the complete type of X-linked congenital stationary night blindness in patients with different mutations in the NYX gene
- 2002
-
Ingår i: Graefe's Archive for Clinical and Experimental Ophthalmology. - : Springer Science and Business Media LLC. - 1435-702X .- 0721-832X. ; 240:10, s. 822-828
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To describe the clinical phenotype of the complete type of X-linked congenital stationary night blindness (CSNB1) with different types of mutations in the NYX gene. Methods: The clinical and genetic data from 18 male patients with eight different mutations from two ophthalmological institutes were reviewed. The variability in refractive error, reduced visual acuity and full-field electroretinogram (ERG) recordings was examined. Results Parameters were quantitatively analyzed based on the classification of mutations according to their predicted effect on protein structure and function. CSNB1 patients with mutations changing structurally conserved residues (n=12) tended to have a lower degree of myopia than patients with mutations of non-conserved residues (n=6). Visual acuity loss and the 30 Hz flicker ERG recordings were similar in the two groups. Values for the b/a amplitude ratio tended to be clustered in patients carrying the same mutation. Refractive error and the b/a amplitude ratio were highly correlated between the two eyes of an individual. Conclusions: These data suggest correlations between phenotypic expression in CSNB1 and individual genotypes as well as class types of mutations based on the extent of structural amino acid conservation. A high inter-eye correlation suggests that other genetic or environmental factors, rather than chance, play a part in determining the phenotypic diversity in CSNB1.
|
|
| 15. |
- Lindberg, Charlotte, et al.
(författare)
-
Multifocal electroretinogram in branch retinal vein occlusion.
- 2003
-
Ingår i: American Journal of Ophthalmology. - 1879-1891. ; 136:6, s. 1163-1165
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To describe the response from multifocal electroretinography in branch retinal vein occlusion. DESIGN: Prospective observational case control series. METHODS: Multifocal electroretinography was recorded in 15 patients with temporal branch retinal vein occlusion and 21 control subjects using a visual evoked response imaging system. RESULTS: There were significant differences in mean amplitude (P =.01) and latency (P =.001) between thrombotic and nonthrombotic retina in the same eyes, as well as in patients compared with control subjects. CONCLUSION: Responses from multifocal electroretinography demonstrate retinal dysfunction in branch retinal vein occlusion; additional studies will demonstrate whether multifocal electroretinography has a prognostic value.
|
|
| 16. |
|
|
| 17. |
- Ponjavic, Vesna, et al.
(författare)
-
Reduced full-field electroretinogram (ERG) in a patient treated with methotrexate.
- 2004
-
Ingår i: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 82:1, s. 96-99
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To examine retinal function in a patient with decreased vision possibly due to treatment with methotrexate. Methods: Ophthalmological examination included testing of visual acuity (VA), fundus inspection, fundus photography and kinetic perimetry. Retinal function was tested objectively with three electrophysiological methods: full-field electroretinography (ERG), multifocal electroretinography (mfERG) and electro-oculography (EOG). Results: A 13-year-old boy with psoriasis arthritis had been treated with methotrexate on a weekly basis for 8.5 years. After terminating treatment, his VA, which was reduced to 0.3 in both eyes initially, improved during the following 3 years but did not return to normal. No visual field defects were found with kinetic perimetry. The rod and cone responses in the full-field ERG were markedly reduced in b-wave amplitude initially, but grew slowly to nearly normal values 3 years later. After withdrawal of the drug, the mfERG demonstrated normal responses in the macular region. The Arden index in the EOG was normal. Conclusion: Chronic treatment with methotrexate may affect VA, and may reversibly reduce rod and cone function. In patients who use systemic medication and whose vision is reduced, objective evaluation of retinal function with electrophysiological methods is recommended.
|
|
| 18. |
- Ponjavic, Vesna, et al.
(författare)
-
Retinal dysfunction and anterior segment deposits in a patient treated with rifabutin
- 2002
-
Ingår i: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907. ; 80:5, s. 553-556
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To describe the clinical and electrophysiological findings in a young boy with decreased vision possibly due to retinal damage by rifabutin. Methods: An 8-year-old boy with osteomyelitis was referred due to visual disturbance. During a period of 4 years, the boy was examined six times with electroretinography. Ophthalmological examination included testing of visual acuity, slit-lamp inspection, fundus inspection, fundus photography and kinetic perimetry. Two electrophysiological methods were performed for objective evaluation of retinal function, namely full-field electroretinography and multifocal electroretinography. Results: We found a slightly reduced visual acuity, a slowly increasing amount of yellow-white deposits on the posterior surface of the cornea and on the anterior part of the lens, a normal fundus appearance, and normal visual fields. However, the electroretinogram was abnormal on several occasions during therapy with rifabutin, but returned to normal 3 months after withdrawal of the medication. The multifocal electroretinogram returned to normal after the full-field electroretinogram had done so. The anterior chamber deposits still remain. Conclusion: Long-term treatment with rifabutin may have a reversible and previously undescribed side-effect on retinal function. The drug may also accumulate irreversibly on the posterior surface of the cornea and on the anterior surface of the lens. We suggest that objective evaluation of retinal function with electrophysiological methods should be performed in patients with visual disturbance during treatment with rifabutin.
|
|
| 19. |
- Schatz, Patrik, et al.
(författare)
-
Macular appearance by means of OCT and electrophysiology in members of two families with different mutations in RDS (the peripherin/RDS gene).
- 2003
-
Ingår i: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907. ; 81:5, s. 500-507
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To describe the phenotype using electroretinography and optical coherence tomography (OCT) in members of two families with different mutations in RDS. Methods: DNA was extracted from blood samples and used for mutation screening by denaturing gradient gel electrophoresis (DGGE) and nucleotide sequencing of RDS exons. Patients were examined with clinical evaluation, full-field electroretinography (ERG), multifocal electroretinography (mfERG) and OCT. Results: An Arg-46 stop codon conversion and a Ser-125 Leu substitution were found, respectively, in affected members of the two families. Phenotypes included retinitis pigmentosa, central areolar choroidal dystrophy, macular dystrophy and adult vitelliform maculopathy. The vitelliform lesion was clearly delineated on OCT, but mfERG showed preserved function. Optical coherence tomography showed attenuation of retinal reflectivity in two cases. Conclusion: By combining traditional investigations with mfERG and OCT, we were able to obtain a more refined evaluation of contributing macular and generalized retinal dysfunction, respectively, in patients with hereditary retinal disease.
|
|
| 20. |
|
|
| 21. |
- Sharon, D, et al.
(författare)
-
Mutated alleles of the rod and cone Na-Ca+K-exchanger genes in patients with retinal diseases
- 2002
-
Ingår i: Investigative Ophthalmology & Visual Science. - 1552-5783. ; 43:6, s. 1971-1979
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE. To study the possible involvement of the rod (SLC24A1) and cone (SLC24A2) Na-Ca+K exchanger (NCKX) genes in retinal diseases. METHODS. DNA was collected from unrelated patients with retinal disease, mainly from North America. A human genomic library was screened with the cone NCKX cDNA, and hybridizing clones were sequenced to determine the genomic organization of the SLC24A2 gene. The single-strand conformation polymorphism (SSCP) technique and direct sequencing were used to screen the patients' DNA for mutations in SLC24A1 and SLC24A2. The effect of selected missense changes on protein function was tested by measuring potassium-dependent Na-Ca exchange of the mutant proteins expressed in insect cells. RESULTS. Twenty-seven novel sequence changes were found in the rod NCKX gene, 21 of which are unlikely to be pathogenic, because they did not cosegregate with the disease or did not affect conserved regions of the protein. Of the remaining six, two were frameshift mutations found in one patient each. If translated, these alleles would encode nonfunctional proteins. Three of the six possibly pathogenic mutations were missense changes located in conserved regions, and their protein functions were assayed. Only one (Ile992Thr) had a significantly low level of exchanger function, but it was found in two unrelated patients who were heterozygotes with different retinal diseases, and this mutation could not be unequivocally associated with either disease. The last of the six changes is likely to create a new splice acceptor site. The genomic organization of the cone NCKX gene was determined, and it contained 11 exons with a few splice variants. Fifteen novel sequence changes were identified in the cone exchanger gene in patients with a cone dysfunction or degeneration. Only three of these sequence changes, all missense changes found in heterozygous patients, were considered possibly pathogenic. Functional analysis showed only a slight reduction in the activity of the corresponding mutant proteins. CONCLUSIONS. Although variant alleles of the rod and cone NCKX genes were found, none could be definitively associated with a specific retinal disease. The human phenotype associated with mutant exchanger alleles remains unknown.
|
|
| 22. |
- Thiselton, DL, et al.
(författare)
-
A comprehensive survey of mutations in the OPA1 gene in patients with autosomal dominant optic atrophy
- 2002
-
Ingår i: Investigative Ophthalmology & Visual Science. - 1552-5783. ; 43:6, s. 1715-1724
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE. To characterize the spectrum of mutations in the OPA1 gene in a large international panel of patients with autosomal dominant optic atrophy (adOA), to improve understanding of the range of functional deficits attributable to sequence variants in this gene, and to assess any genotype-phenotype correlations. METHODS. All 28 coding exons of OPA1, intron-exon splice sites, 273 bp 5' to exon 1, and two intronic regions with putative function were screened in 94 apparently unrelated white patients of European origin with adOA by single-strand conformational polymorphism (SSCP)-heteroduplex analysis and direct sequencing. Clinical data were collated, and putative mutations were tested for segregation in the respective families by SSCP analysis or direct sequencing and in 100 control chromosomes. Further characterization of selected splice site mutations was performed by RT-PCR of patient leukocyte RNA. Staining of mitochondria in leukocytes of patients and control subjects was undertaken to assess gross differences in morphology and cellular distribution. RESULTS. Twenty different mutations were detected, of which 14 were novel disease mutations (missense, nonsense, deletion-frameshift, and splice site alterations) and six were known mutations. Mutations were found in 44 (47%) of the 94 families, included in the study. Ten new polymorphisms in the OPA1 gene were also identified. Mutations occur throughout the gene, with three clusters emerging: in the mitochondrial leader, in the highly conserved guanosine triphosphate (GTP)-binding domain, and in the -COOH terminus. Examination of leukocyte mitochondria from two unrelated patients with splice site mutations in OPA1 revealed no abnormalities of morphology or cellular distribution when compared with control individuals. CONCLUSIONS. This study describes 14 novel mutations in the OPA1 gene in patients with adOA, bringing the total number so far reported to 54. It is likely that many cases of adOA are due to mutations outside the coding region of OPA1 or to large-scale rearrangements. Evaluation of the mutation spectrum indicates more than one pathophysiological mechanism for adOA. Preliminary data suggests that phenotype-genotype correlation is complex, implying a role for other genetic modifying or environmental factors. No evidence was found of pathologic changes in leukocyte mitochondria of patients with adOA.
|
|
