1. |
- Carlsson, Per-Inge, 1959-, et al.
(author)
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GJB2 (Connexin 26) gene mutations among hearing-impaired persons in a Swedish cohort
- 2012
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In: Acta Oto-Laryngologica. - London, United Kingdom : Informa Healthcare. - 0001-6489 .- 1651-2251. ; 132:12, s. 1301-1305
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Journal article (peer-reviewed)abstract
- Conclusion: The most common mutation in the Swedish population was Connexin 26 (C×26) 35delG, which indicates that the percentage of Swedish persons with C×26 mutations and polymorphisms in the GJB2 gene among non-syndromic hearing-impaired (HI) persons is comparable to the rest of Europe. The results strongly support a Swedish policy to offer all children with diagnosed hearing impairment genetic tests for the C×26 35delG mutation.Objectives: The aim of the present study was to search for mutations in the GBJ2 gene among Swedish persons with non-syndromic hearing impairment to further clarify how common these mutations are in Sweden, one of the northernmost countries in Europe.Methods: Seventy-nine patients with non-syndromic hearing impairment participated in the study. For 87% of the participants, a pure tone audiogram showed a severe or profound hearing impairment. Dried blood spots on filter paper, taken at 3-5 days of age in the Swedish nationwide neonatal screening programme for congenital disorders and saved in a biobank, were used for the molecular genetic analyses.Results: The total number of subjects with one or two pathologic mutations or a mutation of unknown consequence found in the GJB2 gene was 28 of 79 (35%). Nineteen (19) persons (24%) were homozygotes for the 35delG mutation.
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2. |
- Hederstierna, Christina, et al.
(author)
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The prevalence of Connexin 26 mutations in the Swedish population
- 2005
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In: Audiological Medicine. - : Informa Healthcare. - 1651-386X .- 1651-3835. ; 3:3, s. 154-158
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Journal article (peer-reviewed)abstract
- Mutations in GJB2, the gene encoding the protein Connexin 26, have been shown to account for as much as 50% of autosomal recessive, non-syndromic childhood hearing loss (ARNSHL). Early, correct diagnosis and intervention have greatly improved the possibilities for these children in learning and developing language skills. In recent years, many reports from varied parts of the world have described the local scene of mutations in Connexin 26. The prevalence differs with geographic location and assessment procedures. Mutations in Connexin 26 have until recently been identified in very few cases in Sweden, Norway and Denmark, and nationwide population samples have not been studied in the Scandinavian countries. In this study we present the results of a large nationwide and a regional study of the prevalence of the 35delG, L90P and 167delT mutations of the GJB2 gene in Sweden. A total of 2052 samples (dried blood spots) were analysed. 1501 samples were collected representing all of Sweden and 551 samples from northern Sweden. The allele frequencies in Sweden were found to be 35delG, 0.83%; L90P, 0.30%; and 167delT, 0%. The prevalence of mutations in Connexin 26 in Sweden seems to be comparable to that in other northern European countries.
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3. |
- Sörensen, Lene, et al.
(author)
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Expanded Screening of One Million Swedish Babies with R4S and CLIR for Post-Analytical Evaluation of Data.
- 2020
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In: International journal of neonatal screening. - : MDPI AG. - 2409-515X. ; 6:2
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Journal article (peer-reviewed)abstract
- Sweden has one neonatal screening laboratory, receiving 115 to 120 thousand samples per year. Among the one million babies screened by tandem mass spectrometry from November 2010 until July 2019, a total of 665 babies were recalled and 311 verified as having one of the diseases screened for with this methodology, giving a positive predictive value (PPV) of 47% and an incidence of 1:3200. The PPV was high (41%) already in the first year after start of screening, thanks to the availability of the collaborative project Region 4 Stork database. The PPV is presently 58%. This improvement was achieved by the implementation of second-tier analyses in the screening for methylmalonic aciduria, propionic aciduria, isovaleric aciduria, and homocystinuria, and the employment of various post analytical tools of the Region 4 Stork, and its successor the collaborative laboratory integrated reports.
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