Effects of 24-bp Indel Mutation Within the AHR Gene on Litter Size in the Akkaraman Sheep Breed

Year 2025, Volume: 31 Issue: 3, 709 - 713, 29.07.2025

Ercan Soydan , Koray Kırıkçı

https://doi.org/10.15832/ankutbd.1579655

Abstract

The aryl hydrocarbon receptor (Ahr) is a transcription factor that is involved in a variety of biological processes, such as cell proliferation, growth and the immune system. Previous investigations have asserted the importance of Ahr gene in female reproduction. However, there are limited studies on the exact mechanisms of the Ahr gene on sheep litter size. Therefore, this study aimed to investigate the 24-bp indel mutation in region 3 of the Ahr gene in Akkaraman sheep, and its impact on litter size. A total of 100 blood samples were used for the study. Genomic DNA was obtained from whole blood. Following the polymerase chain reaction (PCR) analysis, all animals were genotyped based on the result of the agarose gel image. In the study, a 24-bp indel mutation was found, and tree genotypes (II, ID and DD) were detected in Akkaraman sheep. The ID (Insertion/deletion) genotype (59%) was the most common, followed by DD (deletion/deletion) (36%) and II (Insertion/insertion) (5%). In addition, the association analyses showed that the indel mutation within the Ahr gene had a significant influence on litter size.

Keywords

Sheep , Reproduction , Fecundity , Aryl hydrocarbon receptor , Polymorphism

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