臺灣地區臺灣鏟頷魚族群遺傳結構之研究
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Date
1999-06-??
Authors
林弘都
黃生
Hung-Du Lin, Shong Huang
Journal Title
Journal ISSN
Volume Title
Publisher
國立臺灣師範大學生命科學學系
Department of Life Science, NTNU
Department of Life Science, NTNU
Abstract
本研究係利用同功酵素電泳探討臺灣地區臺灣鏟頷魚之族群遺傳結構。總共檢測了11個水系，13個族群，446個個體。在19種同功異構酵素中，得到34個基因座，其中有變異之基因座為12個，平均多型性基因座比例為5.6%;每一個基因座之平均對偶基因數為1.1；平均觀測異質度(HO)為0.020，平均理論異質度(HE)為0.019。利用F-統計分析結果，族群之近交係數(FIS)為-0.026，顯示臺灣鏟頷魚族群內個體為逢機交配，族群間的變異度指數FST)為0.506，族群間呈現高度分化;換算成基因交流值(Nm)為0.244，表示族群間基因交流受到極大的限制;遺傳歧異度(GST)為0.498，顯示約50%的遺傳歧異度是存於族群間的。族群間遺傳距離由0.000到0.063，遺傳距離和地理距離呈現相關，由群叢分析(UPGMA)得知，臺灣鏟頷魚可分為南、北兩群和立霧溪獨立的一群。這些結果顯示，臺灣鏟頷魚傾向於逢機交配，族群間由於基因交流不順暢，產生高度的遺傳分化，水系的阻隔和地區性選汰(local selection)可能為造成族群高度分化的主因。
Genetic structure of Varicorhinus barbatulus (Pellegrin) was examined by using isozyme techniques. Among 13 studied populations, it was found that genetic differentiation was high (FST=0.506). Data of genetic distance analysis showing that there are positive correlations between genetic and geographic groups, i.e. Northern Taiwan, Southern Taiwan and Liwu river, respectively. Gene flow among groups seems to be low (Nm=0.244). Overall survery, genetic variability of this species is still high (HE=0.019). These results indicated that high genetic diversity (GST=0.498) of V. barbatulus is suggested to be due to random mating (FIS=-0.026) and low gene flow and/or local selection due to the isolated river system in Taiwan. However, inbreeding coefficient in overall population (FIT=0.493) was unusually high may indicated that Wahlund effect to e existed in V. barbatulus populations.
Genetic structure of Varicorhinus barbatulus (Pellegrin) was examined by using isozyme techniques. Among 13 studied populations, it was found that genetic differentiation was high (FST=0.506). Data of genetic distance analysis showing that there are positive correlations between genetic and geographic groups, i.e. Northern Taiwan, Southern Taiwan and Liwu river, respectively. Gene flow among groups seems to be low (Nm=0.244). Overall survery, genetic variability of this species is still high (HE=0.019). These results indicated that high genetic diversity (GST=0.498) of V. barbatulus is suggested to be due to random mating (FIS=-0.026) and low gene flow and/or local selection due to the isolated river system in Taiwan. However, inbreeding coefficient in overall population (FIT=0.493) was unusually high may indicated that Wahlund effect to e existed in V. barbatulus populations.