There are two different inheritance patterns of EDS. They are known as
autosomal dominant and autosomal recessive. It is important to remember
that regardless of the pattern of inheritance, we have no control over
which genes we pass on to our children.
In Autosomal Dominant inheritance, only one gene from the parent needs to be
functioning improperly for an individual to be affected. When an
affected person has children, there is a 50% chance with each pregnancy
that the parent will pass on the changed gene to his/her children.
Therefore there is a 50–50 chance
that the child will be affected, regardless of the sex of the child. A
person who does not carry the changed gene is not affected and can not
pass the gene on to his/her children. EDS types that are inherited in
the autosomal dominant fashion include the Classical Type,
Hypermobility Type, Vascular Type
, and Arthrochalasia Type. Most cases
od EDS seem to follow the autsomal dominant pattern of inheritance.
In Autosomal Recessive inheritance, the parent must carry both changed
genes to be affected. A person who has one working gene and one
non–working (changed) gene is said to be a gene carrier. When two
people who carry the same recessive
gene in common have children, there is a 25% chance that the child will
have two working genes and be unaffected; a 50% chance that the child
will be a gene carrier like his/her parents; and a 25% chance that the
child will carry both recessive genes and be affected. These percentage
risks apply to each pregnancy. Types of EDS which are inherited as
autosomal recessive are the Kyphoscoliosis Type and the Dermatosparaxis
Type, but are uncommonly seen types of EDS.