Vol. 46 No. 5, 2007
Phylogeography and Identification of a 187-bp-Long Duplication within the Mitochondrial Control Region of Formosania lacustre (Teleostei: Balitoridae)
Tzi-Yuan Wang1,2, Chyng-Shyan Tzeng1,*, Hui-Yu Teng1, and Tiffany Chang2
1Department of Life Science, National Tsing Hua University, 101 Kuang-Fu Road, Sec. 2, Hsinchu 300, Taiwan
2Genomics
Research Center, Academia Sinica, 128 Academia Road, Sec. 2, Nankang,
Taipei 115, Taiwan. Tel: 886-2-27898756. Fax: 886-2-27898757. E-mail:
d868210@life.nthu.edu.tw
Tzi-Yuan Wang, Chyng-Shyan Tzeng, Hui-Yu Teng, and Tiffany Chang (2007) An unusually long duplication was first discovered within the mitochondrial control region of the hillstream loach, Formosania lacustre.
Over 68% of the 22 heteroplasmic individuals with the duplication were
concentrated in the Tadu and Choshui Rivers of west-central Taiwan.
This unusual duplication was located in the R1-repeated region of the
mitochondrial genome, which includes a partial tRNAPro and
the 5' -end control region. The duplication has a tendency to form
secondary hairpin structures. For the phylogeographic analysis, the
mitochondrial control region of 68 individual loaches from 11 different
river systems (10 in Taiwan and 1 in mainland China) were amplified and
sequenced. Nested clade analysis divided these loach populations into 2
distinct groups: northern and central groups. Higher and lower FST
values were respectively revealed in the northern and central groups.
Unexpectedly, a newly recorded population was established in this
study. This population was previously classified as F. stigmata, but the mtDNA lineage analysis and morphological comparison indicated a strong similarity of this population with F. lacustre.
Furthermore, the nested clade analysis indicated a long-distance
dispersal route from central Taiwan to the mainland China; the mainland
population later dispersed into northern Taiwan during recent ice ages.
We concluded that colonization between the mainland China and central
Taiwan was a major influence leading to the low genetic divergence and
recent recolonization of F. lacustre.
Key words: Heteroplasmy, Polymorphism, Balitoridae, D-loop, Crossostoma lacustre.
*Correspondence: Tel: 886-3-5742765. Fax: 886-3-5742765. E-mail: labtcs@gmail.com
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