1. |
- Entesarian, Miriam, et al.
(författare)
-
A chromosome 10 variant with a 12 Mb inversion [inv(10)(q11.22q21.1)] identical by descent in the Swedish population
- 2009
-
Ingår i: American Journal of Medical Genetics. - : Wiley Interscience. - 0148-7299 .- 1096-8628 .- 1552-4825 .- 1552-4833. ; 149A:3, s. 380-386
-
Tidskriftsartikel (refereegranskat)abstract
- We identified a paracentric inversion of chromosome 10 [inv(10)(q11.22q21.1)] in 0.20% of Swedish individuals (15/7,439) referred for cytogenetic analysis. A retrospective analysis of 8,896 karyotypes from amniocenteses in Sweden revealed a carrier frequency of 0.079% (7/8,896) for the inversion. Cloning and detailed analysis of the inversion breakpoint regions show enrichment for interspersed repeat elements and AT-stretches. The centromeric breakpoint coincides with that of a predicted inversion from HapMap data, which suggests that this region is involved in several chromosome 10 variants. No known gene or predicted transcript are disrupted by the inversion which spans approximately 12 Mb. Carriers from four non-related Swedish families have identical inversion breakpoints and haplotype analysis confirmed that the rearrangement is identical by descent. Diagnosis was retrieved in 6 out of the 15 carriers referred for cytogenetic analysis. No consistent phenotype was found to be associated with the inversion. Our study demonstrates that the inv(10)(q11.22q21.1) is a rare and inherited chromosome variant with a broad geographical distribution in Sweden.
|
|
2. |
- Hilton, Emma N, et al.
(författare)
-
Left-sided embryonic expression of the BCL-6 corepressor, BCOR, is required for vertebrate laterality determination.
- 2007
-
Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 16:14, s. 1773-1782
-
Tidskriftsartikel (refereegranskat)abstract
- Oculofaciocardiodental (OFCD) syndrome is an X-linked male lethal condition encompassing cardiac septal defects, as well as ocular and dental anomalies. The gene mutated in OFCD syndrome, the BCL-6 corepressor (BCOR), is part of a transcriptional repression complex whose transcriptional targets remain largely unknown. We reviewed cases of OFCD syndrome and identified patients exhibiting defective lateralization including dextrocardia, asplenia and intestinal malrotation, suggesting that BCOR is required in normal laterality determination. To study the function of BCOR, we used morpholino oligonucleotides (MOs) to knockdown expression of xtBcor in Xenopus tropicalis, thus creating an animal model for OFCD syndrome. The resulting tadpoles had cardiac and ocular features characteristic of OFCD syndrome. Reversed cardiac orientation and disorganized gut patterning were seen when MOs were injected into the left side of embryos, demonstrating a left-sided requirement for xtBcor in lateral determination in Xenopus. Ocular defects displayed no left-right bias and included anterior and posterior segment disorders such as microphthalmia and coloboma. Expression of xtPitx2c was shown to be downregulated when xtBcor was depleted. This identifies a pathway in which xtBcor is required for lateral specification, a process intrinsically linked to correct cardiac septal development.
|
|
3. |
|
|
4. |
- Mansouri, Mahmoud Reza, et al.
(författare)
-
Alterations in the expression, structure and function of progesterone receptor membrane component-1 (PGRMC1) in premature ovarian failure
- 2008
-
Ingår i: Human molecular genetics. - : Oxford University Press (OUP). - 1460-2083 .- 0964-6906. ; 17:23, s. 3776-83
-
Tidskriftsartikel (refereegranskat)abstract
- Premature ovarian failure (POF) is characterized by hypergonadotropic hypogonadism and amenorrhea before the age of 40. The condition has a heterogeneous background but genetic factors are demonstrated by the occurrence of familial cases. We identified a mother and daughter with POF both of whom carry an X;autosome translocation [t(X;11)(q24;q13)]. RNA expression studies of genes flanking the X-chromosome breakpoint revealed that both patients have reduced expression levels of the gene Progesterone Receptor Membrane Component-1 (PGRMC1). Mutation screening of 67 females with idiopathic POF identified a third patient with a missense mutation (H165R) located in the cytochrome b5 domain of PGRMC1. PGRMC1 mediates the anti-apoptotic action of progesterone in ovarian cells and it acts as a positive regulator of several cytochrome P450 (CYP)-catalyzed reactions. The CYPs are critical for intracellular sterol metabolism, including biosynthesis of steroid hormones. We show that the H165R mutation associated with POF abolishes the binding of cytochrome P450 7A1 (CYP7A1) to PGRMC1. In addition, the missense mutation attenuates PGRMC1's ability to mediate the anti-apoptotic action of progesterone in ovarian cells. These findings suggest that mutant or reduced levels of PGMRC1 may cause POF through impaired activation of the microsomal cytochrome P450 and increased apoptosis of ovarian cells.
|
|
5. |
|
|
6. |
- Stattin, Eva-Lena, et al.
(författare)
-
Brachydactyly type A1 associated with unusual radiological findings and a novel Arg158Cys mutation in the Indian hedgehog (IHH) gene
- 2009
-
Ingår i: European Journal of Medical Genetics. - : Elsevier. - 1769-7212 .- 1878-0849. ; 52:5, s. 297-302
-
Tidskriftsartikel (refereegranskat)abstract
- Brachydactyly type A1 (BDA1; MIM 112500) is characterized by shortness or absence of the middle phalanx of the hands and feet. The condition is caused by heterozygous mutations in the Indian hedgehog (IHH) gene or a yet unidentified gene on chromosome 5p13. We investigated six affected members of a large Swedish family segregating autosomal dominant brachymesophalangia. Affected individuals show hypoplasia of the ulnar styloid processes, ulna minus, osteoarthritis, normal length of all distal phalanges and shortening or absence of the middle phalanges. Stationary ossicles or sesamoid bones were observed at the metacarpal heads in all patients. Genetic analysis of the family showed that the IHH-gene was linked to the disease (Z(max) 3.42 at theta 0.00) and sequence analysis of IHH revealed a novel c.472C > T transition in all affected family members. The mutation results in a p.158Arg > Cys substitution located in the highly conserved amino-terminal domain of IHH. This domain is of importance for the interaction between IHH and the Patched receptor. Our combined findings add radiological findings to the BDA1 phenotype and confirm a critical functional domain of IHH.
|
|
7. |
- Stattin, Eva-Lena, 1960-
(författare)
-
Clinical and genetic studies of three inherited skeletal disorders
- 2009
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Mutations in genes of importance for cartilage development may lead to skeletal malformations, chondroskeletal dysfunction and increased susceptibility to degenerative joint disease. Characterization of these mutations and identification of molecular pathways for the corresponding gene products have contributed to our understanding of mechanisms regulating skeletal patterning, endochondral ossification and joint formation. A five generation family segregating autosomal dominant osteochondritis dissecans (OCD) was identified. Affected family members presented with OCD in knees, hips and elbows, short stature, and early osteoarthritis. A genome wide scan and a multipoint linkage analysis identified aggrecan (ACAN) as a prime candidate gene. DNA sequence analysis of the ACAN-gene revealed heterozygosity for a missense mutation (c.6907G>A) in affected subjects, resulting in a p.V2303M substitution in the aggrecan G3 domain C-type lectin. This domain is important for the interaction with other proteins in the cartilage extracellular matrix. To determine the effect of the V2303M substitution on secretion and interaction, we performed binding studies with recombinant mutated and wild type G3 proteins. We found decreased affinity or complete loss of interaction between V2303M aggrecan and fibulin1, fibulin2 and tenascin-R. Analysis of articular cartilage from an affected family member confirmed that V2303M aggrecan is produced and present. In search for gene mutations associated with multiple epiphyseal dysplasia (MED) we considered the ACAN-gene a likely candidate. The ACAN-gene was analysed in 39 individuals with MED and screened negative for mutations in six previously known MED genes. Sequence analysis revealed a heterozygous missense mutation (c.1448G>T) in one adult male and compound heterozygous missense mutations (c.1366T>C and c.836G>A) in a five year old boy with healthy parents, each of them carrier for one of the mutations. A large family segregating autosomal dominant brachymesophalangia and OCD in finger joints was characterised. The clinical presentation in six affected family members was consistent with the diagnosis Brachydactyly type A1, in this family characterized by shortening of the middle phalanges, short ulnar styloid process, flattening of the metacarpal heads and mild osteoarthritis. The condition may be caused by mutations in the Indian hedgehog gene (IHH) or a yet unidentified gene on chromosome 5p13. Sequence analysis of the IHH-gene in affected individuals revealed a novel C to T transition (c.472C>T) leading to a p.158Arg>Cys substitution. Residue 158 in IHH is highly conserved throughout evolution and molecular structure modelling of IHH suggests that the R158C substitution leads to a conformational change at the site of interaction with the IHH-receptor. This supports that the substitution causes Brachydactyly type A1 in this family. In summary, we report on the clinical, radiological and molecular genetic characteristics of the three skeletal disorders OCD, MED and BDA1. Our results provide a novel molecular mechanism in the pathophysiology of familial osteochondritis dissecans confirming the importance of aggrecan C-type lectin for cartilage function. We also show that ACAN-gene mutations may be associated with MED extending the spectrum of skeletal dysplasias associated with the aggrecan gene. Finally, we report on a novel missense mutation in a conserved region of the IHH-gene associated with BDA1.
|
|
8. |
- Stattin, Eva-Lena, 1960-, et al.
(författare)
-
Familial osteochondritis dissecans associated with early osteoarthritis and disproportionate short stature
- 2008
-
Ingår i: Osteoarthritis and Cartilage. - London : Elsevier BV. - 1063-4584 .- 1522-9653. ; 16:8, s. 890-6
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Familial osteochondritis dissecans (OCD) is a rare disorder characterised by disturbed chondro-skeletal development, disproportionate growth and deformation of the skeleton. DESIGN: We identified a five-generation family with 15 living affected members from Northern Sweden. The disorder was diagnosed with a case definition of OCD in at least one joint. RESULTS: Main clinical findings consisted of OCD in knees and/or hips and/or elbows, disproportionate short stature and early osteoarthritis (OA). There were no radiological indications of epiphyseal dysplasia. Anthropometric measurements of affected individuals showed short stature, a high ratio between sitting height and total height, a relatively normal arm span and head circumference. In 12 of 15 cases, onset was during late childhood or adolescence and OA had developed in seven of those patients. CONCLUSIONS: Our observation suggests that OA is a frequent complication in familial OCD even though the lesions appear before closure of physis.
|
|
9. |
|
|
10. |
- Timby, Niklas, et al.
(författare)
-
Early onset autosomal dominant spinocerebellar ataxia with miosis : Four cases
- 2008
-
Ingår i: European journal of paediatric neurology. - London : Saunders. - 1090-3798 .- 1532-2130. ; 12:1, s. 38-40
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Previously, at least 29 different forms of autosomal dominant spinocerebellar ataxias (SCAs) have been described. We describe a family with four members through three generations with autosomal dominant ataxia in combination with miosis and hyperreflexia. This family's ataxia does not match any of the previously described SCAs and is probably a novel form of SCA. To continue with the search for the genetic background of this disease, more cases are needed.
|
|