Polymorphism of Genes Potentially Affecting Growth and Body Size Suggests Genetic Divergence in Wild and Domestic Reindeer (Rangifer tarandus) Populations

Abstract

Background/Objectives: A combination of increased human presence in the Arctic zone alongside climate change has led to a decrease in the number of wild reindeer (Rangifer tarandus). Studying the genetic potential of this species will aid in conservation efforts, while simultaneously promoting improved meat productivity in domestic reindeer. Alongside reducing feed costs, increasing disease resistance, etc., acquiring genetic variation information is a crucial task for domestic reindeer husbandry. This study thus identified highly informative molecular genetic markers usable for assessing genetic diversity and breeding purposes in reindeer. Methods: We analyzed gene polymorphism that may potentially affect animal growth and development in populations of wild (Taimyr Peninsula) and domestic reindeer, including Nenets and Evenk breeds. We screened these populations for polymorphisms by sequencing the GH, GHR, LCORL and BMP2 genes. Results: Following generation of gene sequences, we compared the alleles frequency in the surveyed populations and their genetic divergence. Some loci lacked polymorphism in wild reindeer, unlike domestic breeds. This could suggest a selection-driven microevolutionary divergence in domestic reindeer populations. An isolated domestic population from Kolguyev Island appeared to be genetically remote from continental reindeer. Conclusions: Molecular genetic markers associated with economically important traits in reindeer can be further developed using the data obtained. Monitoring wild reindeer populations and better utilizing the genetic potential of domestic animals will depend on a panel of these marker genes. By using this marker panel, the amount of time spent on selection efforts will be greatly reduced to enhance meat performance during reindeer breeding.

Keywords: BMP2; GH; GHR; LCORL; body size; genes; genetic divergence; growth; polymorphism; reindeer Rangifer tarandus.

Figure 1

Sampling sites of the reindeer (Rangifer tarandus) in the Far North of Russia. Populations/breeds designation: KgNen, Nenets breed, Kolguyev Island; NarNen, Nenets breed, Naryan-Mar; NoNen, Nenets breed, Nosok; TaiWild, wild reindeer, Taimyr Peninsula; SurEv, Evenk breed, Surinda.

Figure 2

Reindeer (Rangifer tarandus) in the Far North of Russia: (a) Nenets breed that has a smaller body size, (b) a larger Evenk breed, (c) Nenets breed on Kolguyev Island and (d) reindeer in the Taimyr Peninsula. Credit: (a,b,d) own authors’ photographs; (c) https://commons.wikimedia.org/wiki/File:Ice-bound_on_Kolguev_-_a_chapter_in_the_exploration_of_Arctic_Europe_to_which_is_added_a_record_of_the_natural_history_of_the_island_(1895)_(14779560514).jpg (accessed on 27 November 2024) (by J.T. Nettleship, 1895; no known copyright).

Figure 2

Reindeer (Rangifer tarandus) in the Far North of Russia: (a) Nenets breed that has a smaller body size, (b) a larger Evenk breed, (c) Nenets breed on Kolguyev Island and (d) reindeer in the Taimyr Peninsula. Credit: (a,b,d) own authors’ photographs; (c) https://commons.wikimedia.org/wiki/File:Ice-bound_on_Kolguev_-_a_chapter_in_the_exploration_of_Arctic_Europe_to_which_is_added_a_record_of_the_natural_history_of_the_island_(1895)_(14779560514).jpg (accessed on 27 November 2024) (by J.T. Nettleship, 1895; no known copyright).

Figure 3

Occurrence frequencies of four SNP alleles found in the GH gene [23]. Populations/breeds designation: TaiWild, wild reindeer, Taimyr Peninsula; SurEv, Evenk breed, Surinda; NoNen, Nenets breed, Nosok; NarNen, Nenets breed, Naryan-Mar; KgNen, Nenets breed, Kolguyev Island.

Figure 4

Hierarchical clustering dendrograms showing the genetic diversity differences between the studied reindeer populations/breeds. Hierarchical clustering trees were built using SNP genotyping data (a) at GHR (present study) and GH [23] loci, and (b) at LCORL (present study and [24]) and BMP2 [25] loci. Populations/breeds designation: (a) SurEv, Evenk breed, Surinda; NoNen, Nenets breed, Nosok; KgNen, Nenets breed, Kolguyev Island; NarNen, Nenets breed, Naryan-Mar; TaiWild, wild reindeer, Taimyr Peninsula; (b) Nenets, Nenets breed; Wild, wild reindeer, Taimyr Peninsula; Evenk, Evenk breed.

Figure 5

Occurrence frequencies of eight SNP alleles observed in the LCORL gene in domestics (of the Evenk and Nenets breeds) and the wild reindeer (present study and [24]).

Figure 6

Occurrence frequency of 11 SNP alleles identified in the BMP2 gene in domestics (of the Evenk and Nenets breeds) and the wild reindeer [25].

Figure 7

Genetic divergence plots based on occurrence frequencies of SNP alleles. Hierarchical clustering trees were built using SNP allele frequencies identified (a) at GHR (present study) and GH [23] loci, and (b) at LCORL (present study and [24]) and BMP2 [25] loci. Populations/breeds designation: (a) KgNen, Nenets breed, Kolguyev Island; NarNen, Nenets breed, Naryan-Mar; NoNen, Nenets breed, Nosok; SurEv, Evenk breed, Surinda; TaiWild, wild reindeer, Taimyr Peninsula; (b) Wild, wild reindeer, Taimyr Peninsula; Nenets, Nenets breed; Evenk, Evenk breed.