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- Konrádsson, K, et al.
(författare)
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Gör balansprov på alla döva småbarn! : Tidig upptäckt av Ushers syndrom ökar möjligheterna till kommunikation vid senare dövblindhet
- 1998
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Ingår i: Läkartidningen. - 0023-7205. ; 95:5, s. 81-379
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Although deaf children depend upon sight for communication, retinitis pigmentosa is present in 6 per cent of those with a profound hearing deficit. Usher syndrome type 1 (USH-1) is an autosomal recessive disease characterised by profound hearing impairment, absent vestibular function, and progressive loss of vision due to retinitis pigmentosa. Owing to the severe handicap of the combined disorders, early diagnosis of USH-1 is of crucial importance. The profound hearing deficit is often detected at hearing tests in infancy, but as the sight problems do not develop until later diagnosis is often delayed. The diagnosis of Usher's syndrome is established by electroretinography (ERG), as confirmation of the retinitis pigmentosa is a prerequisite. As the progressive deterioration of sight hinders the use of sign language, a cochlear implant constitutes an invaluable aid at an early age. Early diagnosis is thus of both medical and educative importance. To avoid delay in diagnosis past the age when optimal results may be expected from a cochlear implant, a screening test was sought for infants with profound hearing loss to identify those at increased risk of USH-1, for whom ERG is a priority. Although conventional vestibular testing methods are not well tolerated by infants, with recently developed equipment for video or CCI) (charge-coupled device) camera inspection of eye movements, vestibular screening can now be performed in the office. In our experience it is possible to screen most infants, given a careful approach by the investigator. Children with clinically diagnosed USH-1, without any vestibulo-ocular reflex, manifested no vestibular responses during 'video-nystagmoscopy' when rotated on the parent's lap, preliminary findings strongly suggest that vestibular function should be tested in all children with a profound congenital hearing deficit, as it is important for children with USH-1 to be provided with a cochlear implant permitting aural reception of communication from the environment at an early age, because of the progressive deterioration of vision and the ultimate double handicap.
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| 2. |
- Ekström, Ulf, et al.
(författare)
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A Swedish family with a mutation in the peripherin/RDS gene (Arg-172-Trp) associated with a progressive retinal degeneration
- 1998
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Ingår i: Ophthalmic Genetics. - : Swets & Zeitlinger Publishers. - 1744-5094 .- 1381-6810. ; 19:3, s. 149-156
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To clinically characterize a Swedish family with autosomal dominant retinitis pigmentosa due to a mutation, Arg-172-Trp, in the peripherin/RDS gene. METHODS: Full clinical evaluation including kinetic visual field testing, measurement of dark-adaptation threshold, and full-field electroretinography in seven patients with autosomal dominant retinitis pigmentosa and three healthy family members. Denaturing gradient gel electrophoresis (DGGE) was used for mutation screening in seven patients and six healthy members of the family. RESULTS: Three of four siblings from the middle generation and four of the younger generation were heterozygous for the peripherin /RDS Arg-172-Trp mutation. The mutation segregated with the disease. Visual acuity decreased progressively with age and visual fields were moderately constricted in young patients, while central scotoma and constriction of the fields were detected in the family members above 50 years of age. The results from full-field electrography were comparable with a widespread retinal degeneration. CONCLUSIONS: Earlier, the peripherin/RDS Arg-172-Trp mutation was associated primarily with a macular degeneration phenotype. One previous study indicated that this mutation also can give rise to a degeneration of the more peripheral parts of the retina. In the present study, a widespread retinal degeneration is seen in the patients above 50 years of age, carrying the Arg-172-Trp mutation.
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| 3. |
- Ekström, Ulf, et al.
(författare)
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Detection of alterations in all three exons of the peripherin/RDS gene in Swedish patients with retinitis pigmentosa using an efficient DGGE system
- 1998
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Ingår i: Molecular Pathology. - 1366-8714. ; 51:5, s. 287-291
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: To develop a sensitive mutation screening procedure suitable for routine analysis of the peripherin/RDS gene, and to estimate the nature and prevalence of peripherin/RDS gene mutations in Swedish patients with autosomal dominant retinitis pigmentosa. METHODS: To make the method as sensitive as possible, as many as eight segments, covering the three exons and the flanking intron sequences of the peripherin/RDS gene, were analysed by denaturing gradient gel electrophoresis. A group of 38 Swedish patients with a clinical diagnosis of autosomal dominant retinitis pigmentosa were screened for mutations in the peripherin/RDS gene. RESULTS: Three point mutations were found in four of the patients and five polymorphisms were defined. One mutation in exon 1, R172W, has been described previously in other ethnic groups as causing a macular degeneration. Another mutation, in exon 2 and causing the substitution F211L, was found in two unrelated patients. A third mutation, resulting in the likely non-pathogenic substitution S289L, as well as a polymorphism not reported previously, was found in exon 3. CONCLUSIONS: The screening procedure described allows detection of mutations in all of the exons, including the polymorphic 5' and 3' ends of the gene, and is therefore suitable for routine screening of peripherin/RDS gene defects in patients with autosomal dominant retinitis pigmentosa. The frequency of mutations found in the Swedish patient group indicates that defects in the peripherin/RDS gene might be a more common cause of autosomal dominant retinitis pigmentosa than was thought previously.
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| 4. |
- Ekström, Ulf, et al.
(författare)
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Phenotypic expression of autosomal dominant retinitis pigmentosa in a Swedish family expressing a Phe-211-Leu variant of peripherin/RDS
- 1998
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Ingår i: Ophthalmic Genetics. - : Swets & Zeitlinger Publishers. - 1744-5094 .- 1381-6810. ; 19:1, s. 27-37
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To characterize the clinical phenotype, with emphasis on electrophysiology, of members of a Swedish family with autosomal dominant retinitis pigmentosa due to a novel mutation, F211L, in the peripherin/RDS gene. METHODS: Nine patients with autosomal dominant retinitis pigmentosa and two healthy family members underwent a full clinical evaluation including kinetic visual field testing, measurement of dark adaptation threshold, and full-field electroretinography. Blood samples were collected and DNA analysis was performed using denaturing gradient gel electrophoresis (DGGE). RESULTS: The grandfather, six of seven siblings from the middle generation, and two young boys carried the mutation F211L in the peripherin/RDS gene. The mutation segregated with the clinical presentation of disease. Fundus examination revealed mainly macular atrophy. All assessed parameters of retinal function (visual acuity, dark adaptation threshold, visual fields, and full-field electroretinograms) demonstrated a successive reduction with increasing age. Full-field electroretinograms showed a diminished rod response in all affected individuals and a reduction of the cone b-wave amplitudes with increasing age, indicating retinitis pigmentosa. In the affected family members, the disease seems to progress at a similar rate with increasing age. CONCLUSIONS: The peripherin/RDS gene mutation F211L is associated with a clinical phenotype and includes early loss of rod function and successive reduction of cone function with increasing age, but impressively well-preserved visual acuity and visual fields in young and middle-aged patients and moderately reduced vision in the old patient. Compared to previously described phenotypes segregating with mutations in the peripherin/RDS gene, the present family demonstrates a more benign clinical phenotype, which is concordant within the family.
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| 5. |
- Ponjavic, Vesna, et al.
(författare)
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Clinical expression of X-linked retinitis pigmentosa in a Swedish family with the RP2 genotype
- 1998
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Ingår i: Ophthalmic Genetics. - 1744-5094. ; 19:4, s. 187-196
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To examine the clinical phenotype with emphasis on electroretinograms and visual fields in a Swedish family with X-linked retinitis pigmentosa (XLRP) type 2 (RP2), and compare it with Swedish XLRP families with the RP3 genotype. METHODS: Three affected brothers and their carrier mother were examined clinically and with kinetic perimetry, dark adaptation thresholds, and full-field electroretinograms. The genotype was determined by haplotype analysis using polymorphic markers spanning the XLRP loci at the short arm of the X chromosome. RESULTS: The phenotype was consistent in the three affected males. The first subjective symptom was night blindness and the visual disability was more pronounced with increasing age. Affected individuals had a slight decrease in visual acuity and were emmetropic. They demonstrated a pathologically elevated final rod threshold. The visual fields were constricted in a somewhat atypical pattern. The three patients had an early presenting atypical cataract with multiple opacities. The fundus appearance was typical for RP with narrowing of retinal vessels and bone spicule pigmentations. The rod electroretinograms were extinguished in both eyes of the patients. The combined rod-cone responses as well as the isolated cone responses were severely reduced in amplitude; however, atypically for RP, the implicit time for the isolated cone responses was normal. The carrier female demonstrated normal ophthalmological findings, with the exception of two minimal pigmentations in the lower quadrants of the left eye. Haplotype analysis demonstrated that the disease in this family segregates with the RP2 locus. CONCLUSION: The phenotype of the studied RP2 family is associated with early onset of night blindness, emmetropia, a slight decrease in visual acuity, constriction of visual fields, and atypical cataract formation. Electroretinograms demonstrate severe rod dysfunction and surprisingly normal cone response implicit times which may indicate a milder disease progression. These findings are different from earlier descriptions of the RP2 and RP3 phenotypes.
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