Replication, C- and fluorescent chromosome banding patterns in European whitefish, Coregonus lavaretus L

The chromosome complement of Coregonus lavaretus was investigated using C-banding, DAPI and CMA sub(3) fluorescent stainings, and replication banding techniques. Diploid chromosome number was 2n = 80, and the arm number was NF = 100. Karyotype consisted of 8 pairs of metacentrics, 2 pairs of submetacentrics, 2 pairs of subtelocentrics and 28 pairs of acrocentrics, gradually decreasing in size, and of 0-4 supernumerary chromosomes. Chromomycin A sub(3) staining revealed the location of nucleolar organizer regions (NORs), showing that examined fish possessed two pairs of submetacentric-subtelocentric (sm-st) NOR-bearing chromosomes. Staining with DAPI revealed the distribution of AT-rich regions. The use of in vivo 5-bromodeoxyuridine (BrdU) incorporation technique induced highly reproducible replication bands. All banding patterns obtained in the study allowed identification of numerous chromosome pairs in the Coregonus lavaretus karyotype. Chromosome 1 showed individual variation in the amount of C-positive heterochromatin resulting in the length polymorphism of this pair. Replication banding pattern in European whitefish showed differences between three forms of the first chromosome pair.