Imperforate anus

Imperforate anus - Anorectal malformations
Other names	Anorectal malformations
An X-ray showing imperforate anus
Specialty	Medical genetics

An imperforate anus or anorectal malformations (ARMs) are birth defects in which the rectum is malformed. ARMs are a spectrum of different congenital anomalies which vary from fairly minor lesions to complex anomalies.^[1] The cause of ARMs is unknown; the genetic basis of these anomalies is very complex because of their anatomical variability. In 8% of patients, genetic factors are clearly associated with ARMs.^[2] Anorectal malformation in Currarino syndrome represents the only association for which the gene HLXB9 has been identified.^{[clarification needed][1][3]}