New CNTN3 gene polymorphisms associated with meat productivity indicators in Manychsky Merino sheep

Abstract

Introduction. Marker-assisted selection is a method based on the accelerated selection of livestock using DNA markers for valuable traits. Results from a genome-wide association study on the frequency of specific single nucleotide polymorphisms, utilizing DNA biochips, identified candidate genes, which included the CNTN3 gene. Direct experimental data on CNTN3 gene expression in Merino sheep are currently unavailable. Thus, a knowledge gap exists concerning structural variants of the CNTN3 gene and their association with productive traits.
Aim. To study the structure of the CNTN3 gene in Manychsky Merino sheep and to identify polymorphisms associated with meat productivity indicators for their subsequent application in marker-assisted selection.
Materials and methods. The research studied genomic DNA extracted from blood samples of Manychsky Merino rams. Sequencing was performed using the NovaSeq 6000 genome sequencer (Illumina, Inc., USA). Genome assembly was conducted using the ARS-UI_Ramb_v2.0 reference from the NCBI (National Center for Biotechnology Information). The nomenclature of the Human Genome Variation Society was used to describe the identified single nucleotide substitutions.
Results. Sequencing of the CNTN3 gene revealed 7,232 polymorphisms. Among these, groups of polymorphisms (27297434, 27297454, 27297488) demonstrating the highest statistical significance of associations with meat productivity traits in sheep were identified. Novel structural variants were discovered: a duplication at position 27337036 and single nucleotide substitutions at loci 27097370 and 27418238.
Conclusion. The obtained results of the CNTN3 gene structure analysis indicate its association with live weight. The identified polymorphisms can be used as molecular markers for the selection of Merino sheep.

To cite: Baranova D.E., Krivoruchko A.Yu., Yatsyk O.A., Likhovid N.G. New CNTN3 gene polymorphisms associated with meat productivity indicators in Manychsky Merino sheep. Agrarian Bulletin of the North Caucasus. 2025;15(4):24-33. https://doi.org/10.31279/2949-4796-2025-15-4-24-33