<prompt> Down Syndrome, All are seen exceptt 14 ; 21Trisomy 21t 11:14t 15:21  <response>: Majority of translocations in Down syndrome are fusions at the centromere between chromosomes 13,14,15,21 and 22.These are known as Robeson I an translocation. t11:14 is not seen in down syndrome. Reference : Nelson TB of pediatrics 19th edition pg 402. 