Using Telomeric Length Measurements and Methylation to Understand The Karyotype Diversification of Ctenomys Minutus (A Small Fossorial Mammals)

Abstract

The genus Ctenomys has been widely used in karyotype evolution studies due to the variation in their diploid numbers (2n), which range from 2n = 10 to 2n = 70. Ctenomys minutus is characterized by intraspecific variation in diploid number (2n = 42, 46, 48, and 50), which makes it an interesting model to investigate the genomic instability mechanisms that have led to different cytotypes in this species. We aimed to contribute to the knowledge about telomeres’ role in chromosomal instability and global DNA methylation in the genome evolution of C. minutus. This study found that telomere length differs between cytotypes, but only for females (50a<46a,48a,42), although methylation was also higher, no significant difference was shown. It was also shown that young individuals, regardless of cytotype, had the longest telomere and the most methylated DNA, although only the last was statistically significant. Despite this, there is still much to be answered, although new cytotypes seem to have emerged within the distribution of parental cytotypes by the accumulation of different chromosomal rearrangements.