Vascular is a critical fibrillar collagen comprised of

Vascular Ehlers-Danlos syndrome (EDS)
is an inherited connective tissue disorder known as the most severe form of EDS.
Vascular EDS is the result of a heterozygous mutation, typically a point
mutation of glycine, in the type III collagen produced by the COL3A1 gene
(Mizuno). Mutations in the gene lead to defects in the collagen it produces or leads
to reduced amounts of collagen created. The disease is genetically inherited as
an autosomal dominant trait. Vascular, or type IV, EDS is phenotypically
characterized with patient symptoms including translucent and fragile skin that
is hyper-extensible and marked with atrophic cutaneous scars. Individuals with
vascular EDS are likely to have complications involving arterial, digestive and
urinary facets. They have bowels and arteries that are prone to rupture
spontaneously and bruise easily. Further, these individuals have severely
fragile internal organs and arteries and often suffer from receding gums and
varicose veins. The major cause of death within vascular EDS is arterial
ruptures. The median age of death of individuals with this disease is fifty
years. (GARD)  

            Collagens
are a protein family that serve as strength and support systems for many bodily
tissues. They are the most abundant protein in mammals and account for nearly
30% of their protein content. Collagen molecules have a rigid, rod-like
structure that resists stretching. Type III collagen is a critical fibrillar collagen
comprised of three ?1(III) chains supercoiled around each other, forming a
right-handed triple helix with about three amino acids per turn (Xin). The
helix is stabilized by the presence of glycine as every third residue. Mutations
of type III collagen include sing-base substitutions of glycine to another
amino acid and mRNA splicing defects (Kuiv). Type III collagen is discharged by
fibroblasts and other types of mesenchymal cells. The protein provides
structure and strength to connective tissues throughout the body. Type III
collagen is found in tissues exhibiting elastic properties such as skin, lungs,
intestinal walls, and the walls of the blood vessels and is the second most
abundant collagen of soft tissues to type I collagen. Type III collagen is vital
for the development of the skin and the cardiovascular system. The protein is crucial
for maintaining the healthy and stable physiological functions of organs in
adults.

            Type
III collagen is a major constituent of the extracellular matrix. The protein,
along with type I collagen, provides tissues with tensile strength and
influence cell attachment and migration. Within the dermis layer, 90% of found
collagen is type I and 10% is type III collagen. When compared to type I
collagen fibers, those of type III have a smaller diameter and are better able
to withstand deformation. Strands of type III collagen compose reticular fibers
that build a highly ordered cellular network and provide a supporting network.
Reticular fibers form reticular connective tissue and provide a stroma to
support the liver, lymphoid organs, capillary endothelia, and muscle fibers. These
fibers are mainly found in the basement membrane. The formed connective tissue
act as capsules for organs and joints.