A comparative study of karyotypes and chromosomal location of rDNA genes in important liver flukes Fasciola hepatica and Fascioloides magna (Trematoda: Fasciolidae)

摘要: Chromosomal characteristics, i.e., number, size, morphology, and location of ribosomal DNA (rDNA) clusters were examined in two medically important liver flukes, Fasciola hepatica Fascioloides magna (Fasciolidae), using conventional Giemsa staining fluorescent situ hybridization (FISH) with 18S rDNA probe. A comparison F. karyotypes confirmed significant differences all chromosomal features. Whilst the karyotype comprised ten pairs chromosomes (one metacentric nine medium-sized subtelocentrics submetacentrics; 2n = 20, n = 1 m + 5 sm + 4 st; TCL = 49.9 μm), complement was composed 11 submeta-metacentrics (2n = 22, n = 9 st + 1 sm + 1 sm-m; TCL = 35.2 μm). Noticeable found mainly length morphology first chromosome pair. It 9.0 μm long while subtelocentric 4.7 magna. Although FISH probe revealed a single cluster genes both species, conspicuous interspecific displayed by loci (i.e., NORs). The signals on short arms fifth homologous pair hepatica; however, they detected pericentromeric regions tenth observed cytogenetic interpreted terms evolution fasciolid flukes; may be regarded phylogenetically younger than present paper provides pilot study molecular cytogenetics within group hermaphroditic digenetic flukes.