Chromosomal location of bovine RTEL. Bovine RTEL gene is mapped to chromosome 13 by radiation hybrid mapping (RH mapping) and fluorescence in situ hybridization (FISH). The numbers indicated the PCR results of RH mapping, 1 and 0 represent positive and negative signals respectively. RTEL was mapped to bovine chromosome 13, placed 10.87 cR from the CHGB mark (LOD>3.0). The FISH and G-banding results shown in the bottom further confirmed the RH mapping result, specific hybridization signals (arrows) were observed on homologous chromosomes 13q2.2 comparing to standard GTG-banded cattle karyotype.