RESUMO
Introduction: Down syndrome (DS) or trisomy 21 is the mostcommon type of chromosomal abnormalities in new-born.There are three types regular (Free) Trisomy 21, Translocationand Mosaic Trisomy 21. One third cases of Down syndrome,clinical diagnosis may not be confirmed. Therefore, in thisstudy we aimed to confirm the suspected Down syndromepatients by a cytogenetic analysis and also evaluate the riskfactors associated with Down syndrome.Material and methods: Total 30 suspected Down syndromepatients with aged between days 2 to 20 years old wereincluded in this study, on the basis of well-defined inclusioncriteria. The cytogenetic analysis, karyotype was carriedout for all 30 suspected patients from peripheral blood andstaining with Giemsa (G-Banding).Results: Total of 30 children were included in which 16patients with Down syndrome and 14 with normal. Regular(Free) Trisomy 21 was found in 93.75% patients andtranslocation was seen in 6.25% case. Whereas Mosaicdown syndrome was not seen in any cases. Among Downsyndrome, 10 (62.50%) were males. The mean maternal ageat birth was significantly higher (31.94±3.04 years) in DownsyndromeConclusion: Our results suggest that regular trisomy 21 ismore common in Down syndrome cases. Moreover, highermaternal age was the major risk factor for Down’s syndrome