Guinea pig (Cavio cambayo) 5S rRNA genes map to 7q2, 20q2 and 30q2 shown by an R‐banded karyotype with PNA‐FISH

摘要

Compared with the mouse and the rat genomes rather few genes have been assigned to specific localizations in the guinea pig (The Jackson Laboratory, Mouse Genomic Informatics, www.Informatics.jax.org). 5S rRNA is part of the ribosome that is important to protein synthesis, and extensive studies of 5S rRNA and the 5S rRNA genes from many organisms have been compiled (Szymanski et al. 2000). The 5S rRNA gene contains 121 bp that are highly conserved in mammalian species. The 5S rRNA genes are clustered in tandem repeats of various sizes, approximating 100–200 repeats in the haploid genome in man (S?rensen and Frederiksen 1991), in Macaca fascicularis (Riff Jensen and Frederiksen 2000), in mouse (Hallenberg et al. 1994), and in rat (Frederiksen et al. 1997).Gene mapping increasingly shows the need for informative karyotypes, so due to the lack of any recent karyotype of the guinea pig we felt inclined to propose one. In the present work we have used it to map the 5S rRNA genes to 7q2, 20q2 and 30q2, respectively, applying a modified PNA-FISH protocol by Lomholt et al. (2000).