The Opitz G/BBB Family Network
- Online support and information for families with Opitz G/BBB Syndrome. Provides families with easy-to-read information about the syndrome.
- http://www.opitznet.org

NORD: Opitz Syndrome
- A look at the alternate names, a general discussion and resources.
- http://www.rarediseases.org/search/rdbdetail_abstract.html?disname=Mannosidosis

Family Village
- Opitz G Syndrome information and contact links.
- http://www.familyvillage.wisc.edu/lib_optz.htm

Zach's Opitz Syndrome Site
- Offers information, a family's experience with this syndrome and links to the Opitz Family Network.
- http://www.opitzsyndrome.com

National Library of Medicine: OS
- Opitz syndrome, the synonyms, a summary and a list of major features.
- http://www.nlm.nih.gov/mesh/jablonski/syndromes/syndrome498.html

Canadian Opitz Family Network
- A description of Opitz G/BBB Syndrome.
- http://www.apollos.net/arena/opitz/definition.html