Naletsana

a Trisomy 21 ke boloetse boo ngoana a tsoaloang le bona bo bakang kholofalo kelellong. Ka tloaelo, li-chromosome li tsamaea ka bobeli, empa bana ba hlahang ba e-na le trisomy ba na le chromosome ea boraro ho e ’ngoe ea tsena tse tsamaeang ka bobeli. Trisomy 21 e ama chromosome 21.