Oculodentodigital syndrome
Overview
Oculodentodigital syndrome (ODD syndrome) is an extremely rare genetic condition that typically results in small eyes, underdeveloped teeth, and syndactyly and malformation of the fourth and fifth fingers. It has also been called oculo-dento-digital syndrome, oculodentodigital dysplasia (ODDD), and oculodentoosseous dysplasia (ODOD). It is considered a kind of ectodermal dysplasia.
Symptoms
* Small eyes * Small corneas * Fine porous iris * Short opening between the eyelids * Epicanthal fold
Causes
ODDS is an inherited disorder caused by mutations in GJA1, also known as the connexin-43 gene. This gene is located on chromosome 6. ODDS is most commonly inherited in an autosomal dominant pattern. In this type, family histories are common and the condition may be present in several generations. A person with ODDS has a 50% of having an affected child. The exact signs and symptoms may vary from person to person, even within the same family. Instances of autosomal dominant inheritance with no family history also exist, in which a person develops ODDS from a new mutation that occurred by chance during their conception. There are reports of these chance mutations being possibly associated with an older average age for the father.
Diagnosis
Genetic testing from a blood sample is available for those suspected to have a clinical diagnosis. This testing studies the GJA1 gene carefully to look for disease-causing mutations. An abnormal genetic test result is one that finds a mutation in a person's copy of GJA1. Finding this mutation confirms the diagnosis of ODDS. Once a mutation has been found, other at-risk family members can also be tested. Genetic testing can also be offered during the second trimester of a pregnancy via an amniocentesis procedure, if a couple desires such information during that time. Genetic testing should be offered in conjunction with careful genetic counseling for the affected individual, the family members, or the expectant couple. A diagnosis is more often made after the careful identification and study of a person's symptoms and family history. A diagnosis may be suspected by a team of specialists, including an ophthalmologist, dermatologist, dentist, orthopedist, medical geneticist, neurologist, and otolaryngologist.
Prognosis
ODDS can involve a combination of severe medical complications in some cases. Since no two people experience the exact same type of symptoms, it is impossible to predict the ones a child newly diagnosed with the condition will have. No specific lifespan ranges are known, but might be lower in those who have more serious medical concerns. Newer medical treatments continue to offer hope for those with ODDS and their families.