Karyotype of various type of 21-trisomy Standard type(47,XY/XX, +21) mosaicism(46/47+21) Translocation (eg: 46, -13, +t(13q: 21q)
• Standard type (47,XY/XX,+21) • masaicism（46 / 47 + 21） • Translocation（eg：46, -13,+t(13q;21q） Karyotype of various type of 21-trisomy
2121 2121 八 Disjunction of chromosome 21 IOSIS 2121 gamete 21 21 21 212121 21 212121 oosperm 21 monosomy 21-trisomy Pathogenesis of standard type 2/-tr chromosome 2/ duri
21 21 21monosomy 21-trisomy Pathogenesis of standard type 21-trisomy:disjunction of chromosome 21 during miosis Disjunction of chromosome 21 21 21 21 21 21 Germ cells 21 21 21 21 0 21 21 gamete 21 21 21 oosperm miosis
Karyotype of mosaicism/ k8xx著A》八x一汽一 X一一 21-trisomy cell series 3条21号染色体 【 d 、y Normal cell 2 series 2条21号染色体
21-trisomy cell series Normal cell series 3条21 号染色体 2条21 号染色体 Karyotype of mosaicism 21-trisomy
Pat of mosaicism 21-trisomy 2121 Oosperm mitosis 2121 12 八 C First generation Disjunction of chromosome 21 during mitosis 2121 2121 212121 21 A八八 seocnd generation Nondisjunction in early cell division of a normal zygote
mitosis 21 21 Oosperm 21 21 21 21 First generation 21 21 21 21 21 21 21 21 seocnd generation Disjunction of chromosome 21 during mitosis Pathogenesis of mosaicism 21-trisomy Nondisjunction in early cell division of a normal zygote
Translocation flon armof chromosome r I i 21 to chromosome 14 。“点 溪24 7 8 K Example of translocation of 21-trisomy
Translocation of long arm of chromosome 21 to chromoxome 14 Example of translocation of 21-trisomy