C- and NOR-banding karyotype analysis of Nannospalax xanthodon (2n = 52, 2n = 60) and new locality for 2n = 52 cytotype from western Anatolia

Abstract

This study investigated C-heterochromatin and NOR (nucleolar organizer region) characteristics of 2n = 52 and 2n = 60 chromosomal forms of Nannospalax xanthodon (blind mole rat), which are separated by the Sakarya River in Bilecik Province. In addition, a new locality was included to the geographical border of 2n = 52 NF = 70 cytotypes. According to the results of C-banding, centromeric heterochromatin was detected in three pairs of chromosomes and telomeric heterochromatin was detected in three pairs of chromosomes in the 2n = 52 form. Sex chromosomes are negative heterochromatins. In the 2n = 60 form, a telomeric heterochromatin region was found in seven pairs of chromosomes. The sex chromosomes have centromeric heterochromatin. According to the NOR distributions of chromosomes, in 2n = 52 cytotypes, NOR was detected in the telomeric regions of four bi-armed chromosomes, while in 2n = 60 types active NOR was detected in telomeric regions of three bi-armed chromosomes.