Characterization of Robertsonian and Reciprocal Translocations in Cattle through NGS

Simple Summary This study introduces a novel approach that combines next-generation sequencing (NGS) with cytogenetic technologies to identify chromosomes involved in chromosomal anomalies in cattle. This research focuses on a chromosome anomaly discovered in male Alpine Grey cattle, as well as two previously reported cases of reciprocal translocations (rcp), namely rcp(9;11) and rcp(4;7). Traditional cytogenetic analyses, including Giemsa staining, CBA-banding, RBA-banding, and FISH techniques, were performed. Chromosomes were microdissected from conventional preparations, and the amplified products were sequenced using NGS. The sequencing reads were mapped to the reference genome, and the leverage effect was calculated to identify abnormal reads/Mb values. The results unveiled the specific chromosomes involved in the Alpine Grey cattle anomaly, which were further validated through RBA-banding and FISH analysis. Moreover, the feasibility of this approach on preserved metaphases was demonstrated by analyzing old slides from previously characterized cases.Abstract This study presents a novel approach that combines next-generation sequencing (NGS) and cytogenetic technologies for identifying chromosomes involved in chromosomal anomalies. This research focuses on a chromosome anomaly discovered in male Alpine Grey cattle, as well as two previously reported cases of reciprocal translocations (rcps), namely rcp(9;11) and rcp(4;7). Abnormal chromosomes from Alpine Grey cattle were microdissected from conventional preparations, and the amplified products were sequenced using NGS. The sequencing reads were then mapped to the reference genome, and the leverage effect was calculated to identify abnormal reads/Mb values. The result revealed the presence of rob(26;29), which was further confirmed through traditional cytogenetic analyses such as Giemsa staining, CBA-banding, RBA-banding, and FISH techniques. Furthermore, the feasibility of this approach on preserved metaphases was demonstrated through analysis of old slides from previously characterized cases. The study highlights the challenges involved in identifying and characterizing chromosomal aberrations in bovine species and offers a potential solution for analyzing historical anomalies when fresh blood material is unavailable. The combination of NGS and cytogenetic techniques provides a cost-effective and reliable approach for characterizing chromosomal anomalies in various species, including those identified before the availability of modern banding technologies and FISH mapping using specific molecular markers.