台灣溪哥分爲粗首鱲和平頷鱲兩種,過去研究顯示種內的族群分化與地理分部有關。AFLP是一種選擇性擴增生物基因組DNA限制性片段的方法,此分子遺傳技術方便迅速又可靠,可以精確地提供族群遺傳特性或個體之間的差異性,是釐清台灣溪哥族群結構的絕佳研究方法。使用EcoRI與MseI作爲內切酶,分析總共83個溪哥個體之基因組,選用片段長度40~239bp之AFLP多型性片段共200個,作爲重建台灣溪哥親緣關係樹之基礎資料。以Nei-Li distance tree分析,結果發現粗首鱲(包括NA&SA兩型)、平頷鱲台灣型(TL)和平頷鱲日本型(JL)明顯被分爲三大群,顯示三者之間的族群遺傳結構有明顯的分化。此外,粗首鱲NA與SA之間亦有部份的分化情形。
Two species of freshwater minnow occur in Taiwan, Zacco platypus and Zacco pachycephalus. Previous studies indicate that population genetic differentiations are common within each minnow species. We analyzed genetic relationships for the two species of minnows by using a new DNA markers amplified fragment length polymorphisms (AFLP) for 83 specimens collected from 33 localities of 6 rivers in Taiwan. We used two restriction enzymes (EcoRI and MseI) to digest the genomic DNA for AFLP analysis which realved 200 scorable AFLP loci. Nei-Li distance tree displayed that two genetic groups of Zacco platypus (TL & JL) can be distinguished from Zacco pachycephalus with statistical significance. Moreover, genetic difference was also shown in two geographical groups of Zacco pachycephalus (NA & SA).