Periodontal Ehlers-Danlos syndrome is a rare condition which impacts the complement system.
Chromosome location: 12p13
Genes affected: C1R (12p13.31) and C1S (12p13.31), encoding C1r and C1s of complement
Inheritance: autosomal dominant
Clinical features:
(1) premature loss of teeth associated with a rapidly progressing periodontitis and lack of attached gingiva
(2) joint hypermobility
(3) skin and vascular fragility with easy bruisability
(4) pretibial hyperpigmentation and plaques
(5) microangiopathy with leukoencephalopathy
Defects:
(1) C1r and/or C1s of complement
(2) type III and I collagen
