Wednesday, December 2, 2009

Several models of inheritance

Most types of Ehlers-Danlos syndrome are inherited as an autosomal dominant. This means that you need a single copy of the pathogenic mutation inherited from both parents develop signs and symptoms of the disease. If you inherit the mutation, there's a 50 percent chance that you' ll send the gene on each of your children.

Two types of Ehlers-Danlos syndrome and kyphoscoliosis dermatosparaxis - rained a legacy inherited as an autosomal recessive trait. This means that you have two copies of the mutated gene to develop the disease. If you inherit only one copy, you're a "media" of the disease, but probably won't grow signs and symptoms.

The following table describes how different types of Ehlers-Danlos syndrome are inherited and genetic mutations are involved.

Tuesday, December 1, 2009

Ehlers-Danlos Syndrome Type


Type I
form of severe, affects 43% of patients and is autosomal dominant.
In this way, the clinical symptoms are usually severe.
Patients who have marked a section of skin wounds and scars frequently in various parts of the body.
Surgical sutures heal properly, with a slight dehiscence.
Hypermobility is very strong and affects all parts of the body.
Spontaneous fractures may occur, but an immediate reduction is simple.
Varicose veins and pseudotumors Molluscoida are frequent.
Musculo-skeletal features are easy to find. These features include kyphoscoliosis) Hallus valgus flat foot (eg flat feet and genu recurvatum; contusions are less common in this type than in other forms.
Heart disease, especially heart mitral valve prolapse, are sometimes available.
With a premature rupture of fetal membranes is specific for that type.

Type II are the Mitis, affects 35% of patients and is autosomal dominant.
This group is characterized by a soft light of the functions of type I.
Large scars are often, but the skin has a slightly lower sensitivity and bruisability.
The joints are moderately hyperextensible, and the figures are usually only interested in the body.

Type III the benign hypermobile familial form, affects 10% of patients and is autosomal dominant.
Patients with this variant have no or only minimal changes in the skin, but have a hypermobility affects multiple joints.
This usually results hyperextensibility orthopedic consequences (eg severe osteoarthritis) in the long term.

Type IV which bruises and blood pressure affects 6% of patients and is an autosomal recessive or, sometimes as an autosomal dominant.
This variant is relatively rare.
Clinically, the patients were single, white, translucent skin and the underlying vessels are easily recognizable.
The skin is sensitive, but not expandable.
Molluscoida pseudotumors are many scars and bruises, and hemorrhagic lesions.
Scars and hyperpigmentation are common.
Common Hyperextensibility is rare or absent.
Arterial aneurysms, mitral valve and spontaneous pneumothorax are frequent complications.
Patients also have a low weight and small size.
The prognosis of this type is poor, and the patient \ 's life is shortened.
Sudden death can occur after a visceral perforation or after the collapse of a large vessel, usually a stomach or a ship of the spleen.
Prenatal diagnosis by restriction of polymorphic DNA analysis is possible.
Type V, the X-linked form, affects 5% of patients and is X-linked recessive.
Skin of patients with this form of Ehlers-Danlos syndrome is very elastic and orthopedic frequent.
Bruising and laxity are rare.

Type VI the ocular form, the disease affects about 2% of patients and is an autosomal recessive trait.
Patients of this type are clinically severely affected by the disease.
Unable to perform Translation:invalid result dataPatients may have multiple scars, some of which are hyperpigmented.
Joints are hyperextensible.
This subgroup has eyes only of clinical symptoms. The fragile eye can cause bleeding and retinal detachment, glaucoma and color of the sclera. Outside the world is rare, but possible.
The action of LH in the amniotic fluid can be used to predict the outcome of pregnancy.

Type VII or more arthrochalasis congenita, affects 3% of patients and is an autosomal recessive or autosomal dominant.
Patients with this type of significant hyperextensibility common, but the lesions are less severe than those of other species.
Patients spontaneous dislocation, often with a rapid reduction.
Patients of this type are generally small.

Type VII the form periodontitis is rare and is inherited as an autosomal dominant.
Patients of this type have a dental examination with periodontal gum.
Sagging skin, joint and hyperextensibility bruisability vary.
Gingival resorption and loss of permanent teeth when the patient at the age of 30 years is common.
IX or X-linked cutis laxa type is rare, and a structure in X-linked recessive.
Patients with type IX bilateral bony features on the back.
Rarely the skin and joints are affected.
Chronic diarrhea and outcome of orthostatic hypotension are unique in this group.
The scars are usually visible, because the treatment is poor.
Patients of this type have a defect in intracellular copper-dependent enzymes, similar to that of patients with Menkes syndrome.

Type X (fibronectin deficiency) and type XI (benign hypermobility syndrome) is a rare form of Ehlers-Danlos syndrome. Some suggest that these species are so similar that you are better classified as a category 2

Garry Turner Guinness World Records

Ehlers-Danlos syndrome Garry Turner

Garry Turner, of Caistor, Lincolnshire, England, stretched the skin of his stomach to a distended length of 15.8 cm (6.25 in) on the set of Guinness World Records: Primetime in Los Angeles, California, USA, on October 29, 1999.

Garry has a rare disease called Elhers-Danlos Syndrome, a disease of connective tissue, skin, tendons and internal organs. With this condition, collagen, which strengthens the skin and determines its elasticity is damaged, including a loosening of the skin, and "hypermobility" joints. In severe cases can cause the fatal collapse or rupture of blood vessels.





Monday, November 30, 2009

Ehlers-Danlos syndrome

Ehlers-Danlos syndrome
Ehlers-Danlos syndrome (Cutis hyperelastic) is a group of inherited disorders of connective tissue, caused by an error in the synthesis of collagen (a protein) in connective tissue. Collagen in the connective tissue with the tissue to resist deformation (low elasticity). The skin, muscles, ligaments, blood vessels and internal organs, collagen plays an important and with reduced elasticity, collagen abnormally high, the results of pathology. Depending on the individuals can change the severity of the syndrome varies from mild to fatal. There is no cure and treatment is symptomatic, including close monitoring of the cardiovascular system.

Pathophysiology

Ehlers-Danlos syndrome is a heterogeneous group of inherited disorders of connective tissue characterized by joint hypermobility, skin fragility and laxity. Failure of collagen was only 6 of 11 types of Ehlers-Danlos syndrome identified. Type IV is a small amount of collagen type III classified. Type V and VI are characterized by deficiencies in the hydroxylase and lysyl oxidase, a major modification enzyme in the posttranslational biosynthesis of collagen. Type VII deficiency in amino-terminal procollagen peptidase. Type IX has an unusual copper metabolism. X-Type is not functional plasma fibronectin.

Ehlers-Danlos syndrome type I and II, is the classic version, the identification of the molecular structure in most of those affected are difficult. It may involve mutations causing the COL5A1, COL5A2, and tenascin X genes and should be implicit in the COL1A2 gene. However, in most families with autosomal dominant Ehlers-Danlos disease appears to be linked loci COL5A1 and COL5A2 genes included. Even if half of the mutations cause Ehlers-Danlos syndrome type I and II are capable of COL5A1 gene, a significant proportion of mutations that reduce mutant mRNA due to nonsense-mediated mRNA decay.

Bouma et al evaluated 3 generations in a family with Ehlers-Danlos syndrome type II, the lack of a genome (-2) → G substitution in exon-14 splice acceptor site. The electronic transmission of images of type I collagen fibers in the skin biopsy, has a diameter fibrils heterogeneous object was higher than that of a control sample. The proband was found that a greater percentage of fibers have fibrils and occasional large and small, with a configuration of cauliflower were observed.

Wenstrup and staff identified haploinsufficiency of the COL5A1 gene coding for proalpha1 (V) chain of collagen type V in the classic form of Ehlers-Danlos syndrome. Eight of 28 patients with Ehlers-Danlos syndrome classic were heterozygous for the polymorphism of COL5A1 expression is complete or nearly complete loss of expression of one COL5A1 allele. A third of people with Ehlers-Danlos syndrome classics were COL5A1 mutations, which are haploinsufficiency. These results indicate that requires the formation of normal heterotypic collagen fibrils that contain types I, III, V and the expression of both COL5A1 collagen alleles.

Autosomal recessive type VI Ehlers-Danlos syndrome, also known as kyphoscoliotic type is characterized by neonatal kyphoscoliosis, generalized joint hypermobility, skin fragility, and severe muscle hypotonia at birth. Biochemical, such as a lack of lysyl hydroxylase (LH), the enzyme lysine residues of collagen specific hydroxylysine hydroxyl molecule with 2 important functions and formal. The residues are the sites linking to glucosylgalactose galactose, and act as a precursor to the networking process, collagen is its tensile strength.

More than 20 mutations in the gene for this deficiency and clinical LH1 Ehlers-Danlos syndrome type VI LH has been identified. Yeowell and Walker identified 2 of these mutations in at least 5 unrelated patients: (1) a large overlap of exons 10-16, resulting from homologous recombination of intronic Alu sequences, and (2) a nonsense mutation, Y511X in exon 14 of gene LH1. The two mutations appear to come from a single ancestor gene.

Tenascin-X is a main protein of the extracellular matrix, resulting in lack of a recessive form clinically different syndrome.5 then factors other than collagen or collagen-processing enzymes can cause this syndrome. This module just described may be associated with additional anomalies.

A case with perforation of the colon in a young girl with a fatal outcome, a new mutation in the COL3A1 gene are linked. Crystal structure of human type III in the structure of G991-G1032 cystine knot, both 7 / 2 and 10 / 3 symmetries.

A novel point mutation was found in the vascular type of Ehlers-Danlos syndrome. The mutation is in second position of exon 24 of COL3A1.
The healing of wounds is a typical characteristic of Ehlers-Danlos syndrome, probably a defect in fibroblasts. Healing can be obtained by exogenous type V collagen.
Ehlers-Danlos syndrome in pediatric patients has been shown that defects in 3 genes of glutathione S-transferase family (GSTM1, GSTT1, GSTP1). This leads to the formation of reactive oxygen species. Reduced activity of beta4-galactosyltransferase 7 (beta4GalT-7) is associated with the progeriform Ehlers-Danlos syndrome.