Identification of genes affecting litter size trait in Zandi sheep using random forest method

Document Type : Research Article (Regular Paper)

Authors

1 Department of Animal Sciences, Faculty of Agriculture, College of Agriculture and Natural Resources, University of Tehran, Alborz Province, Karaj, Iran

2 Department of Animal Science, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran

Abstract

Knowledge of the association of single nucleotide polymorphisms with economically important traits is an important tool for breeding programs in the livestock industry. The aim of the present study was to identify important and influential markers of litter size trait in Zandi sheep using genomic data and random forest method. Significant markers including s59645, OAR14_49049707, s51972, OAR12_19965932, OAR14_40046813, s61144 and OAR2_53988637 were identified by the machine learning method (random forest) for the litter size. The identified markers were associated with new genes including STEAP2, CCNP, RAB11FIP2, GPATCH2, URI1, ROPN1L and SKAP1. Gene ontology study showed that genes discovered by the random forest play roles in key biological functions such as cellular metabolic processes, DNA-templated transcription, biosynthetic process, embryonic skeletal system morphogenesis, embryonic skeletal system development, regulation of gene expression, organ morphogenesis, skeletal system development, and chordate embryonic development. The identified candidate genes provided additional insights into the genetic mechanisms underlying the litter size in Zandi sheep. Furthermore, the important SNP markers identified by the random forest analysis could serve as potential candidates for future functional validation and marker-assisted or genomic selection programs.

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