<prompt> Down Syndrome, All are seen exceptt14 ; 21Trisomy 21t11 : 14t15 :21  <response>: In 95 of cases of Down Syndrome - trisomy of 21Extra chromosome is of maternal in origin1 have mosaic with 46 chromosomes4 have Robertsonian translocation.t13:21t 14 : 21t 15 : 21Very rarely long arm of chromosome 21 is triplicate Partial trisomy 