Relationship of polymorphisms in PITX1, PITX2, LHX3, PROP1 and POU1F1 genes with litter size and growth traits in saanen goats

Growth and reproductive traits, among the most economically critical functional characteristics in animal production, emerge as a result of the interaction between genetic and environmental factors. Understanding the genetic basis of these traits is crucial for developing sustainable selection programs that aim to increase productivity, particularly in goat breeding. However, the fact that multiple genes control these characteristics makes it difficult to explain the effects of genetic variations. The POU1F1 pathway is a crucial pathway that plays a vital role in pituitary development and the regulation of growth and reproductive hormones. Determining the hormones affected by the genes in this pathway and the traits influenced by the pleiotropic genes involved is highly important for both animal health and breeding goals. However, there is insufficient information on this subject in goats. In this context, the aim was to determine the frequencies of the PITX1 (c.490G>A), PITX2 (g.18353T>C), LHX3 (g.8035T>C), PROP1 (c.236C>T), and POU1F1 (c.837T>C and c.771+215C>T) polymorphisms located in the POU1F1 pathway and to demonstrate the relationship of these polymorphisms with growth and reproductive traits in Saanen goats. In the study, a total of 150 Saanen goats were genotyped. The relationship with growth and reproductive traits, including birth weight, litter size, daily weight gain, total weight gain, first breeding weight, body length, heart girth, rump width, rump height, and wither height, was examined. Within this scope, it was determined for the first time in this study that the LHX3 (g.8035T>C) polymorphism was significantly associated with the number of litter size (P<0.05), and the PITX1 (c.490G>A) polymorphism had a tendency to affect birth weight (P<0.1). The findings, presented for the first time in the literature by this study, make significant contributions to elucidating the genetic basis of growth and reproductive traits in goat breeding. The obtained results indicate that the POU1F1 gene pathway and the polymorphisms in related genes can be evaluated as potential molecular markers in future breeding programs.