Currarino triad or syndrome is an autosomal dominant hereditary condition which is characterized by the triad of sacral agenesis abnormalities (abnormally developed lower spine), anorectal malformation (most commonly in the form of anorectal stenosis) and presacral mass consisting of a teratoma, anterior sacral meningocele or both. However only 1 out of 5 cases of Currarino triad has all three abnormalities present.

Currarino triad is considered a spectrum disorder with a wide variation in severity. Up to one-third of the patients are asymptomatic and may only be diagnosed during adulthood only on X-rays and ultrasound examinations that are performed for different reasons. Currarino triad is most often caused by mutations in the MNX1 gene. Treatment depends on the type and severity of abnormalities present, but may involve surgery.

Less frequently, a complex phenotype of Currarino triad can be caused by microdeletions of 7q containing MNX1 (the long arm of chromosome 7 is missing a small piece of DNA which includes MNX1 and other genes).

In some cases, an affected person inherits the mutated gene from an affected parent. In other cases, the mutation occurs for the first time in a person with no family history of the condition. This is called a de novo mutation.

When a person with a mutation that causes an autosomal dominant condition has children, each child has a 50% (1 in 2) chance to inherit that mutation.

A significant interfamilial (between different families) and intrafamilial (within the same family) variability in expression has been found without any definite correlation to the genetic mutations. This means in one family, a parent might only have one very mild feature of Currarino triad while one of their children might have severe forms of all three features and yet another child might have a mild form of one feature and a severe form of another.