SEQUENTIAL IMMUNOCYTOGENETICS, MOLECULAR CYTOGENETICS AND TRANSMISSION ELECTRON-MICROSCOPY OF MICROSPREAD MEIOSIS-I OOCYTES FROM A HUMAN FETAL CARRIER OF AN UNBALANCED TRANSLOCATION
Al. Barlow et Ma. Hulten, SEQUENTIAL IMMUNOCYTOGENETICS, MOLECULAR CYTOGENETICS AND TRANSMISSION ELECTRON-MICROSCOPY OF MICROSPREAD MEIOSIS-I OOCYTES FROM A HUMAN FETAL CARRIER OF AN UNBALANCED TRANSLOCATION, Chromosoma, 106(5), 1997, pp. 293-303
The oocytes of a 17 week human fetus carrying an unbalanced 46,XX,add(
18)(p13) translocation were studied with a sequential combination of m
icrospreading, immunocytogenetics, fluorescence in situ hybridization
(FISH) and transmission electron microscopy. This combination of techn
ologies allowed the collection of data of unique accuracy and resoluti
on. The translocated chromosome was found to be involved in five diffe
rent synaptic configurations. A consistent feature of these configurat
ions was the involvement of a second small bivalent, presumably chromo
some 21 or 22, the normal synapsis of which was often disrupted. We co
nclude that chromosome 21 or 22 was the source of the translocated mat
erial, which was found to be either homologously triply synapsed, hete
rologously synapsed or asynapsed.