Ehlers-Danlos syndrome (EDS) is a heterogeneous group of heritable connective tissue disorders characterized by articular hypermobility, skin extensibility and tissue fragility. Individuals with EDS have a defect in their connective tissue. It is this tissue that provides support to many body parts such as the skin, muscles, ligaments and organs. The fragile skin and unstable joints found in EDS are due to faulty collagen. Collagen is a protein that acts like glue in the body adding strength and elasticity to connective tissue.
There are six major types of EDS. The different types of EDS are classified according to the signs and symptoms that are manifested. Each type of EDS is a distinct disorder that "runs true" in a family. This means that an individual with Vascular Type EDS will not have a child with Classical Type EDS.
HYPERMOBILITY:
Joint hypermobility is the dominant clinical manifestation. Generalized joint hypermobility that affects large (elbows, knees)and small (fingers and toes) joints is evident in the Hypermobility Type. Recurring joint subluxations and dislocations are common occurrences. Certain joints, such as the shoulder, patella, and temporomandibular joint dislocate frequently. The skin involvement (hyperextensibility and/or smooth velvety skin) as well as bruising tendencies in the Hypermobility Type are present but variable in severity.
Chronic joint and limb pain is a common complaint amongst individuals with the Hypermobility Type. Skeletal X-rays are normal. Musculoskeletal pain is early onset, chronic and may be debilitating. The anatomical distribution is wide and tender points can sometimes be elicited.
To date, no distinctive biochemical collagen finding has been identified by researchers. The Hypermobility Type of EDS is inherited in an autosomal dominant manner.
CLASSICAL:
The categorization of the Ehlers-Danlos syndromes began in the late 1960's and was formalized in the Berlin nosology. Over time, it became apparent that the diagnostic criteria established and published in 1988 did not discriminate adequately between the different types of the Ehlers-Danlos syndrome or between the Ehlers-Danlos syndrome and other phenotypically related conditions.
The two known inheritance patterns for EDS include autosomal dominant and autosomal recessive. Specifics regarding genetic inheritance may be found by following the link below. Regardless of the inheritance pattern, we have no choice in which genes we pass on to our children.