Selenium is a micronutrient essential for the life of many organisms. It cannot be found freely in nature due to its high toxicity and thus, it is mainly found being part of selenocystein residues (Sec) in selenoproteins. The selenocystein is the 21st amino acid and it is encoded by the TGA codon, which also functions as a STOP codon. Because of the duality of this, selenoprotein prediction in genomes is challenging and usually, selenocysteins are misanotated.     

The aim of this study is to find out the localization of selenoprotein coding genes in Balaenoptera acutorostrata genome, also known as the common minke whale. To this end, a bioinformatics program has been developed. It implements the use of different tools such as BLAST, exonerate and T-Coffee. The model genomes used for the alignment with the query genome are those from the dolphin (Tursiops truncatus), the human (Homo sapiens) and the horse (Equus caballus).

A total of 25 selenoproteins, 7 Cys-homologs and 7 machinery proteins (of which, one is also included in the selenoprotein group) have been characterized. The obtained results are in concordance with the vertebrates’ selenoproteome and its evolution.  

To sum up, this research represents a step forward in the field of selenoproteins description in mammals, because it provides knowledge of an undescribed specie until the moment.