金线属两个同域穴居物种的mtDNA序列变异

Mitochondrial DNA Sequence Variation of Two Sympatric Cavefishes in Sinocyclocheilus

对洞穴鱼种犀角金线(Sinocyclocheilusrhinocerous)及与之同域的软鳍金线(S.malacopterus)的线粒体细胞色素b基因的部分序列进行了测定和分析。发现两种之间有45个变异位点,占测序总位点的12 89%.其中在密码子第3位置上的变异有33个,占全部变异点的73 33%.转换与颠换比值为6 5∶1.种间遗传距离为12 9%,表明这两个同域种间的血缘关系可能较远。

A 349 bp fragment of mitochondrial cytochrome b gene of two Sympatric cavefishes i.e Sinocyclocheilus rhinocerous and S.malacopterus that lived in the same cave, were sequenced and compared. 45 nucleotide variations were found, and 11of them occurred at the first nucleotide positions of codons related, 2 at the second position. This difference of these two species was very notable. It indicaled that these two sympatrie cavefishes were unlike to derive directly from the recent same ancestry species. They were not most closely related to each other.