a patient with interstitial 5q21 deletion, familial adenomatous polyposis, dysmorphic features, and profound neurologic dysfunction

familial adenomatous polyposis (fap) is a hereditary autosomal dominant cancer syndrome, results from germ line mutation or deletion of the adenomatous polyposis coli (apc) gene on chromosome 5q21. patients with fap suffer from multiple polyps mainly at the colorectal region as well as other parts of the gastrointestinal tract, which has propensity to transform into carcinoma. fap has also been well described in association with various syndromic extra-gastrointestinal manifestations. less commonly, patients with fap present with varying degrees of cognitive dysfunction and developmental delay, though the reason for the association is unclear. herein, we report the case of a male patient born with an interstitial deletion of chromosome 5q, 46,xy, del(5) (q14q23), presenting with familial adenomatous polyposis (fap), profound developmental delay, cognitive dysfunction, and multiple congenital anomalies including talipes equinovarus, agenesis of the corpus callosum, and dysmorphic facial features.