Thirteen pair of Ribs can be seen in all of the following except:

a. Down syndrome(Ref: Pediatric Surgical Diagnosis pg 10, Ref: Nelson's 20/e p 610-615, Ghai 8/e p 637-639)Thirteen pairs of ribs may be seen in:* Aarskog syndrome* Turner syndrome* Holt-Oram syndrome* Alagille syndrome* Incontinentia pigmenti* Fetal akinesia deformation sequence* Idiopathic