| 1. |
- Gkourogianni, Alexandra, et al.
(författare)
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Clinical characterization of patients with autosomal dominant short stature due to aggrecan mutations
- 2017
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - Cary, USA : Oxford University Press. - 0021-972X .- 1945-7197. ; 102:2, s. 460-469
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Tidskriftsartikel (refereegranskat)abstract
- Context: Heterozygous mutations in the Aggrecan gene (ACAN) cause autosomal dominant short stature with bone age (BA) acceleration, premature growth cessation and minor skeletal abnormalities.Objective: Characterize the phenotypic spectrum, associated conditions and response to growth-promoting therapies.Design: Retrospective international cohort study.Patients: Information from 103 individuals (57 female, 46 male) from 20 families with confirmed heterozygous ACAN mutations were included.Methods: Families with autosomal dominant short stature and heterozygous ACAN mutations were identified and confirmed using whole-exome sequencing, targeted next generation sequencing, and/or Sanger sequencing. Clinical information was collected from medical records.Results: Identified ACAN variants showed perfect co-segregation with phenotype. Adult individuals had mildly disproportionate short stature (median height: -2.8 SDS, range: -5.9 to -0.9) and histories of early growth cessation. The condition was frequently associated with early-onset osteoarthritis (12 families) and intervertebral disc disease (9 families). There was no apparent genotype-phenotype correlation between type of ACAN mutation and presence of joint complaints. During childhood, height was less affected (median height: -2.0 SDS, range: -4.2 to -0.6). In contrast to most children with short stature, the majority of children had advanced BA (BA - CA, median: +1.3y; range +0.0 to +3.7y) reflecting a reduction in remaining growth potential. Nineteen individuals had received GH with some evidence of increased growth velocity.Conclusions Heterozygous ACAN mutations result in a phenotypic spectrum ranging from mild and proportionate short stature to a mild skeletal dysplasia with disproportionate short stature and brachydactyly. In several of the families, affected individuals developed early-onset osteoarthritis and degenerative disc disease requiring intervention, suggesting dysfunction of articular cartilage and intervertebral disc cartilage. Additional studies are needed to determine the optimal treatment strategy for these patients.
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| 2. |
- Stattin, Eva-Lena, et al.
(författare)
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SNX10 gene mutation leading to osteopetrosis with dysfunctional osteoclasts
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- Autosomal recessive osteopetrosis (ARO) is a heterogeneous disorder, characterized by defective osteoclastic resorption of bone that results in increased bone density. We have studied nine individuals with an intermediate form of ARO, from the county of Vasterbotten in Northern Sweden. All afflicted individuals had an onset in early infancy with optic atrophy, and in four patients anemia was present at diagnosis. Tonsillar herniation, foramen magnum stenosis, and severe osteomyelitis of the jaw were common clinical features. Whole exome sequencing, verified by Sanger sequencing, identified a splice site mutation c.212 + 1 G > T in the SNX10 gene encoding sorting nexin 10. Sequence analysis of the SNX10 transcript in patients revealed activation of a cryptic splice site in intron 4 resulting in a frame shift and a premature stop (p.S66Nfs * 15). Haplotype analysis showed that all cases originated from a single mutational event, and the age of the mutation was estimated to be approximately 950 years. Functional analysis of osteoclast progenitors isolated from peripheral blood of patients revealed that stimulation with receptor activator of nuclear factor kappa-B ligand (RANKL) resulted in a robust formation of large, multinucleated osteoclasts which generated sealing zones; however these osteoclasts exhibited defective ruffled borders and were unable to resorb bone in vitro.
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| 3. |
- Winbo, Annika, et al.
(författare)
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Sex is a moderator of the association between NOS1AP sequence variants and QTc in two long QT syndrome founder populations : a pedigree-based measured genotype association analysis
- 2017
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Ingår i: BMC Medical Genetics. - : BIOMED CENTRAL LTD. - 1471-2350. ; 18
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Tidskriftsartikel (refereegranskat)abstract
- Background: Sequence variants in the NOS1AP gene have repeatedly been reported to influence QTc, albeit with moderate effect sizes. In the long QT syndrome (LQTS), this may contribute to the substantial QTc variance seen among carriers of identical pathogenic sequence variants. Here we assess three non-coding NOS1AP sequence variants, chosen for their previously reported strong association with QTc in normal and LQTS populations, for association with QTc in two Swedish LQT1 founder populations.Methods: This study included 312 individuals (58% females) from two LQT1 founder populations, whereof 227 genotype positive segregating either Y111C (n = 148) or R518* (n = 79) pathogenic sequence variants in the KCNQ1 gene, and 85 genotype negatives. All were genotyped for NOS1AP sequence variants rs12143842, rs16847548 and rs4657139, and tested for association with QTc length (effect size presented as mean difference between derived and wildtype, in ms), using a pedigree-based measured genotype association analysis. Mean QTc was obtained by repeated manual measurement (preferably in lead II) by one observer using coded 50 mm/s standard 12-lead ECGs.Results: A substantial variance in mean QTc was seen in genotype positives 476 +/- 36 ms (Y111C 483 +/- 34 ms; R518* 462 +/- 34 ms) and genotype negatives 433 +/- 24 ms. Female sex was significantly associated with QTc prolongation in all genotype groups (p < 0.001). In a multivariable analysis including the entire study population and adjusted for KCNQ1 genotype, sex and age, NOS1AP sequence variants rs12143842 and rs16847548 (but not rs4657139) were significantly associated with QT prolongation, + 18 ms (p = 0.0007) and + 17 ms (p = 0.006), respectively. Significant sex-interactions were detected for both sequent variants (interaction term r = 0.892, p < 0. 001 and r = 0.944, p < 0.001, respectively). Notably, across the genotype groups, when stratified by sex neither rs12143842 nor rs16847548 were significantly associated with QTc in females (both p = 0.16) while in males, a prolongation of + 19 ms and + 8 ms (p = 0.002 and p = 0.02) was seen in multivariable analysis, explaining up to 23% of QTc variance in all males.Conclusions: Sex was identified as a moderator of the association between NOS1AP sequence variants and QTc in two LQT1 founder populations. This finding may contribute to QTc sex differences and affect the usefulness of NOS1AP as a marker for clinical risk stratification in LQTS.
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| 4. |
- Wisten, Aase, et al.
(författare)
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Exercise related sudden cardiac death (SCD) in the young — Pre-mortal characterization of a Swedish nationwide cohort, showing a decline in SCD among athletes
- 2019
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Ingår i: Resuscitation. - : Elsevier BV. - 0300-9572 .- 1873-1570. ; 144, s. 99-105
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Tidskriftsartikel (refereegranskat)abstract
- Aims: To study the frequency, etiology, and premortal abnormalities in exercise-related sudden cardiac death (SCD) in the young in Sweden. Methods: All subjects with SCD in 10–35-year olds in Sweden during 2000–10, were included (n = 514). Information about each case was retrieved from death certifications, autopsy- and medical records. The number of SCD in athletes was compared to national figures from 1992-99. Results: Exercise-related SCD occurred in 12% (62/514) of the SCD-population, a majority being men (56/62; 90%). Cardiopulmonary resuscitation (CPR) was started in 87% (54/62). In total, 48% (30/62), had a cardiac diagnosis, symptoms, family history and/or ECG-changes, before the fatal event. The most prevalent autopsy diagnosis was sudden arrhythmic death syndrome (15/62; 24%). The frequency of hypertrophic cardiomyopathy (HCM) and arrhythmogenic right ventricular cardiomyopathy (ARVC) was significantly higher in exercise-related SCD compared to non-exertional SCD. Exercise-related SCD was more common in athletes (21/29) than in non-athletes (41/485) (P < 0.0001). The total number of SCDs/year in athletes 15–35 years old, are approximately halved in 2000-10 compared to the years 1992–99. Conclusion: The increased risk of exercise-related SCD in HCM and ARVC underlines the importance of early detection and eligibility recommendations. There is a major reduction in deaths among athletes in the 2000s, compared to the previous decade. These results may partly be explained by improved acute preparedness for sudden cardiac arrest (CPR, defibrillation), but as a substantial percentage have preceding risk factors, such as symptoms and ECG-abnormalities, increased cardiac screening and increased general awareness, may also play a role.
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| 5. |
- Wisten, Aase, et al.
(författare)
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Sudden cardiac death among the young in Sweden from 2000 to 2010 : an autopsy-based study
- 2017
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Ingår i: Europace. - : OXFORD UNIV PRESS. - 1099-5129 .- 1532-2092. ; 19:8, s. 1327-1334
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Tidskriftsartikel (refereegranskat)abstract
- Aims: To study the incidence and aetiology of sudden cardiac death (SCD) in 1-to 35-year-olds in Sweden from 2000 to 2010.Methods and results: We used the database of the Swedish National Board of Forensic Medicine and the Swedish Cause of Death Registry and identified SCD cases by review of forensic files and death certificates. We identified 552 individuals with SCD in 1-to 35-year-olds; 156 (28%) were women. In 393 (71%), a forensic autopsy had been performed; in 131 (24%), a clinical autopsy had been performed; in 28 (5%) with no autopsy, a cardiac disease was diagnosed before death. The incidence of SCD per 100 000 person-years was 1.3 in 1- to 35-year-olds and 1.8 in 15- to 35-year-olds. In women, the incidence rates yearly decreased during the study period by 11% (95% confidence interval 6.6-14.2). The most common aetiology in 1- to 35-year-olds was sudden arrhythmic death syndrome (31%) and coronary artery disease (15%). In cases with forensic autopsy, death occurred during daily activity (48%), sleep (38%), and physical activity (14%); death was unwitnessed in 60%. Co-morbidity in 15- to 35-year-olds, e.g. psychiatric disorder, obesity, or diabetes, was present in 93/340 (27%) (73 men).Conclusion: The incidence of SCD among 1- to 35-year-olds in Sweden during 2000-10 was 1.3 per 100 000 person-years (28% women); incidence was decreasing in women. Sudden arrhythmic death syndrome was the most common diagnosis. Co-morbidity such as psychiatric disorders and obesity was common among men.
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| 6. |
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| 7. |
- Clewemar, Pantelis, et al.
(författare)
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Expanding the phenotypic spectrum of osteogenesis imperfecta type V including heterotopic ossification of muscle origins and attachments
- 2019
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Ingår i: Molecular Genetics & Genomic Medicine. - : Wiley. - 2324-9269. ; 7:7
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundOsteogenesis imperfecta (OI) is a clinical and genetic heterogeneous group of connective tissue disorders, characterized by bone fragility and a propensity to fracture.MethodsIn this report we describe the clinical phenotype of two patients, a 28‐year‐old woman and her mother (54 years old), both with a history of short stature and multiple fractures.ResultsExome sequencing revealed the recurring IFITM5:c.‐14 C>T variant causing OI type V. Both patients had several fractures during childhood. CT‐scan and scintigraphy showed ossification of the origin and attachment of muscles and hypertrophic callus formation.ConclusionOssification of the origin and attachment of muscles seems to be part of the phenotype in patients with OI type V.
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| 8. |
- Gkourogianni, Alexandra, et al.
(författare)
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Clinical and Radiological Manifestations in a Large Swedish Family with a Pathogenic Heterozygous ACAN Variant
- 2018
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Ingår i: Hormone Research in Paediatrics. - : S. Karger. - 1663-2818 .- 1663-2826. ; 90:Suppl.1, s. 424-424
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Objectives: Heterozygous mutations in the aggrecan gene (ACAN) are associated with idiopathic short stature, with or without advanced bone age (BA), osteochondritis dissecans (OCD) and early onset of severe osteoarthritis (OA). Variable features also include midface hypoplasia, brachydactyly, short thumbs and intervertebral disc degenerative disease.Methods: We reviewed 173 radiographs in 22 individuals (8F:14M), (3shoulders, 10hands, 10wrists, 17spines, 10pelvis, 31hips, 79knees, 5 lower-legs, 4ankles, 4feet).Furthermore 2 computed tomography scans (1hip; 1knee), and 5 magnetic resonance scans (2hips; 3knees). All included individuals belong to a five generation Swedish family with short stature, OCD, and early onset OA (MIM#165800), caused by a pathogenic sequence variant, p.V2303M, in the C-type lectin domain of ACAN.Results: In the group of children (n=6; age ≤15yo; 3F:3M), six had moderately advanced BA (range:6-17.5months). There was no clear sign of a metaphyseal or epiphyseal dysplasia, but subtle defects of the distal radial growth plate were present in four children. There were 3 males with OCD in the knees and one of them also present-ed OCD of the hip, scoliosis and schmorl’s nodes of intervertebral discs. Actually he went through a derotation osteotomy in both hips and later a proximal tibia osteotomy and distal fibula osteotomy.Among 16 adult patients (5F:11M), 16 had OCD (7elbows,4 hips,13 knees, 5 patellas), 13 developed early onset (>40y) OA, (1shoulder, 5elbows, 3 spines, 1 metatarsophalangeal joint, 6 hips, 12 knees, 1 patella). Radiological manifestations of the spine were detected in 4 patients and included 1 scoliosis, 1 spina bifida occulta, 1 platyspondyly, 1 schmorl’s nodes, and 3 with lowering of the intervertebral discs.Moreover 8 adult patients (3F:5M) have been operated, 4 pa-tients had hip replacement (1F:3M;3bilateral;1unilateral) and 5 knee arthroplasties (2F:3M; 3bilateral;2unilateral) in particular 5 patients had tibia osteotomy of which one had combined tibia and fibula osteotomy. We measured all phalanges of eight adult hand x-rays and found no brachydactyly.Conclusions: The pathogenic heterozygous p.V2303M variant in the ACAN gene causes mildly disproportionate short stature with early-onset OA and intervertebral disc degeneration often requiring multiple orthopedic interventions. Radiologic findings, included moderately advanced BA, OCD in knees, hips, and elbows as well as OA in 13 individuals. Further studies are needed to identify preventive measures that may slow the progression of OA and intervertebral disc disease and to determine the role of rhGH to improve final height
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| 9. |
- Hannuksela, Matias, et al.
(författare)
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A novel variant in MYLK causes thoracic aortic dissections : genotypic and phenotypic description
- 2016
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Ingår i: BMC Medical Genetics. - : Springer Science and Business Media LLC. - 1471-2350. ; 17
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Tidskriftsartikel (refereegranskat)abstract
- Background: Mutations in MYLK cause non- syndromic familial thoracic aortic aneurysms and dissections (FTAAD). Very little is known about the phenotype of affected families. We sought to characterize the aortic disease and the presence of other vascular abnormalities in FTAAD caused by a deletion in MYLK and to compare thoracic aortic diameter and stiffness in mutation carriers and non-carriers.Methods: We studied FTAAD in a 5-generation family that included 19 living members. Exome sequencing was performed to identify the underlying gene defect. Aortic elastic properties measured by TTE, MRI and pulse wave velocity were then compared between mutation carriers and non-carriers.Results: Exome sequencing led to the identification of a 2-bp deletion in MYLK (c3272_ 3273del, p. Ser1091*) that led to a premature stop codon and nonsense-mediated decay. Eleven people were mutation carriers and eight people were non-carriers. Five aortic ruptures or dissections occurred in this family, with two survivors. There were no differences in aortic diameter or stiffness between carriers and non-carriers of the mutation.Conclusions: Individuals carrying this deletion in MYLK have a high risk of presenting with an acute aortic dissection or rupture. Aortic events occur over a wide range of ages and are not always preceded by obvious aortic dilatation. Aortic elastic properties do not differ between carriers and non-carriers of this mutation, rendering it uncertain whether and when carriers should undergo elective prophylactic surgery.
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| 10. |
- Hannuksela, Matias, 1969-
(författare)
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Familial thoracic aortic aneurysms and dissections : studies on genotype and phenotype
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Thoracic aortic aneurysms and dissections (TAAD) have a genetic component with an estimated 20-25% of the patients having a positive family history. An aneurysm often precedes a dissection. Acute aortic dissections are associated with high mortality and morbidity, even when operated on. Complications due to prophylactic surgery are considerably fewer. Therefore, patients at risk for dissection should be identified, followed-up and evaluated for prophylactic intervention.Aims: 1. To establish reference values for ascending (AoA) and descending aortic (AoD) diameters measured by computed tomography. 2. To study the effectiveness of phenotypic cascade screening in families with an inherited form of thoracic aortic aneurysms and dissections (FTAAD) and to address questions that arise when screening for a genetic disorder is applied. 3. To study the agreement of aortic diameters obtained by TTE and MRI and to study aortic stiffness in individuals from families with FTAAD. 4. To perform exome sequencing in order to identify pathogenic sequence variants causing FTAAD, to characterize the phenotype, and to compare thoracic aortic diameter and stiffness in mutation carriers and non-carriers.Results: Paper I: The diameter of the thoracic aorta increased by 0.17 mm (0.12 – 0.20 mm) per year. The mean sex-related difference in diameter was 1.99 mm (1.28 – 2.60 mm) with men having larger aortas than women. The mean difference in aortic diameter per unit BMI was 0.27 mm (0.14 – 0.44 mm). Upper normal limits for the AoA can be calculated by the formula D (mm)=31+0.16*age and for the AoD by D (mm)=21+0.16*age.Paper II: Of 106 individuals from families with FTAAD but without known thoracic aortic disease, 19 individuals (18%) were identified to have a dilated AoA. The expected number of individuals in this group with an autosomal dominant disease would have been 40 (p<0.0001). In first-degree relatives younger than 40, we found only one individual with a dilated aorta although the expected number of individuals with disease causing mutation would have been 10.Paper III: Of 116 individuals investigated, 21 were identified with thoracic aortic dilatation and 95 individuals with normal thoracic aortic diameter. Aortic stiffness increased with age and diameter. The individuals with aortic dilatation were older than those without (49 vs. 37 years, p=0.001) and showed lower aortic elastic properties. The diameters measured by TTE and MRI correlated strongly (r2=0.93). The mean difference in diameters between the two methods was 0.72 mm (95% CI 0.41-1.02) with TTE giving larger diameters than MRI.Paper IV: From exome sequencing and segregation analysis, a 2-bp deletion in the MYLK gene (c.3272_3273del) was identified to cause FTAAD. The age and the aortic diameter at dissection or rupture varied in the family members. We did not find any differences in aortic diameter, aortic stiffness, or pulse wave velocity between carriers and non-carriers.Conclusions: Thoracic aortic diameter increases with age, and sex and body size are also associated with the diameter. In FTAAD, screening identifies family members with a previously unknown aortic dilatation. However, a normal aortic diameter does not exclude an individual from being a carrier of FTAAD. TTE can be used in follow-up for the ascending aorta. Individuals identified to have a dilated thoracic aorta have increased aortic stiffness compared to individuals with normal thoracic aortic diameter. The MYLK mutation (c.3272_3273del) causes thoracic aortic dissections with variable clinical expression. No differences in aortic stiffness were identified between MYLK mutation carriers and non-carriers.
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