大鳞副泥鳅ZZ/ZW型性别决定的细胞遗传学证据

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

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＋３２ｔ（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。

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.