Mitochondrial DNA tRNA^Leu and tRNA^Ser polymorphism in different pig breeds

Analysis of the sequence of mitochondrial DNA (mtDNA), which has a maternal nature of inheritance, is an effective way of assessing the individual characteristics of commercial lines. The analysis of the sequence variability of the mtDNA tRNA^Ser and tRNA^Leu genes in different pig breeds was carried out. The mtDNA tRNA^Leu1, tRNA^Leu2, tRNA^Ser1, tRNA^Ser2 genes were chosen as the study objects. For the study of the sequences, data on pigs of different breeds were selected from the National Center for Biotechnological Information (NCBI). The sample group included 20 animals. Alignment of nucleotide sequences was performed using the BioEdit program. Sequence analysis showed the presence of polymorphisms in all studied genes. A total of six polymorphic sites are established, which are represented by transitions. Analysis of the gene tRNA^eu showed the presence of A3892G substitution. The polymorphism A3892G in the Wuzhishan and Luchuan pigs was determined in the tRNA^Leu1 gene, and polymorphism C3907T was determined in the Swedish wild boar. Many of the pigs studied had a simultaneous presence of two A12879G and C12883T transitions in the tRNA^Leu2 gene. One transition of A8103G in the tRNA^Ser1 gene was established in Large White pigs of Korean breeding. The polymorphism of the tRNA^Ser2 gene is represented by the translation of T12838C into the Italian wild boar. The highest number of polymorphisms was determined in Large White of Korean and Chinese breeding, as well as in the Italian wild boar. The study of mtDNA polymorphism will allow to establish associative links and develop mtDNA markers that can be used in programs for improving and creating breeding resources in pig breeding.

mPHK^Leul, mPHK^Leu2, swine, mtDNA, sequence, tRNA^Leu1, tRNA^Leu2, tRNA^Ser1, tRNA^Ser2

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