大鳞副泥鳅ZZ/ZW型性别决定的细胞遗传学证据

大鳞副泥鳅是鲤形目、鳅科的鱼类。其2n数为48,核型组成为12m+4sm+32 t(雄性),11m+5sm+32t(雌性)。根据银染带和C带特征分析,证实大鳞副泥鳅为ZZ/ZW型性别决定。Z染色体为中部着丝粒染色体,在其长臂端部有Ag -NOR存在。 W染色体为亚中部着丝粒染色体,在其长臂末端也有Ag-NOR存在,同时还有一深染的居间C带,这是W染色体独有的带纹特征。 Abstract:Paramisgurnus dabryanus belongs to Cypriniformes,Cobitidae.Its 2n is 48.The karyotype formula is 12m+4sm+32t(in male),11m+5sm+32t(in female).According to the Ag-NORs band and C-band patterns,we consider that its sex determination is of ZZ/ZW type.The Z chromosome is a metacentric one with Ag-NORs located on its arm end.The W chromosome is a submetacentric with Ag-NORs located on the terminal of its long arm.There is a darkly stained C-band on the long arm of W chromosome.This band is a characteric of the W chromosome.

The Cytogenetic Evidences of ZZ/ZW Sex Determination in Paramisgurnus dabryanus

Paramisgurnus dabryanus belongs to Cypriniformes, Cobitidae. Its 2n is 48. The karyotype formula is 12m 4sm 32t(in male), 11m 5sm 32t(in female). According to the Ag-NORs band and C-band patterns, we consider that its sex determination is of ZZ/ZW type. The Z chromosome is a metacentric one with Ag-NORs located on its arm end. The W chromosome is a submetacentric with Ag-NORs located on the terminal of its long arm. There is a darkly stained C-band on the long arm of W chromosome. This band is a characteric of the W chromosome.