title: [Analysis of genetic differentiation and phylogenetic relationship between Whitmania pigra and Hirudo nipponia based on ITS sequence].
abstract: OBJECTIVE
  To evaluate the genetic differentiation and phylogenetic relationship between Whitmania pigra Whitman and Hirudo nipponia Whitman.
  
  
  METHODS
  By the sequences of the rDNA internal transcribed spacer (ITS) the molecular phylogenetic tree was constructed by MP method using software MEGA 4.0.
  
  
  RESULTS
  The average length of ITS was 857.2-861.2 bp. The A, T, G and C contents in this fragment were 25.12%, 28.28%, 17.34%, 29.29%, respectively. The GC content was higher than the AT content. Little sequence variation was observed in ITS gene fragments with in species, and transition in only 45 loci was revealed in 14 populations. 14 W. pigra and H. nipponia populations were clustered into 2 groups by MP phylogenetic tree.
  
  
  CONCLUSIONS
  The results also showed that the intraspecific variation was dominated in variation types of W. pigra and H. nipponia. The classification result of W. pigra and H. nipponia and its adulterants based on DNA sequences are not totally consistent with those based on classification. It showed that a little of mutation of base in ITS sequences had occurred in the process of evolution, such as transition cites, transvertion cites among base or base gap.
authors: Institute of Chinese Medicinal Materials, Nanjing Agricultural University, Nanjing 210095, China.
authors: Fei
authors: F
authors: Liu
authors: Qiaosheng
authors: Q
authors: Guo
authors: Hongzhuan
authors: H
authors: Shi
authors: Tian
authors: T
authors: Wang
authors: Shusong
authors: S
authors: Lu