A rare chromosomal anomaly syndrome resulting from a partial deletion of the long arm of chromosome 13. The syndrome has a highly variable phenotype and typical characteristics of varying degrees of intellectual disability and developmental delay, as well as central nervous system malformations (e.g. holoprosencephaly, anencephaly, ventriculomegaly, Dandy-Walker malformation), ocular abnormalities (e.g. hypertelorism, microphthalmia, strabismus, aniridia, retinal dysplasia) and craniofacial dysmorphism (microcephaly, trigonocephaly, large and malformed ears, broad prominent nasal bridge, micrognathia). Cardiac, genitourinary, gastrointestinal and skeletal manifestations have also been reported. [from
SNOMEDCT_US]