APA 7: TWs Editor. (2023, November 21). The Discovery of Albinism Gene in Bison Through a Comprehensive Genetic Map by Researchers. PerEXP Teamworks. [News Link]
Published in G3: Genes, Genomes, Genetics, the study provides a comprehensive account of the creation of a high-resolution reference genome. Utilizing this advanced genome, the researchers pioneered the development of the initial test for genetic mutations, with a primary focus on identifying the mutation accountable for albinism.
Albinism, a rare condition resulting in the absence of pigment, renders animals with a white appearance and red eyes. Historically, albino bison have held religious symbolism for certain Native American Indigenous tribes.
The research also establishes the groundwork for identifying additional genetic variations affecting crucial bison traits, including those influencing the health and production value of this species.
Dr. James Derr, a professor of veterinary pathobiology and genetics at VMBS, spearheaded the team responsible for the initial bison genome in 2015. He assembled a group for this new reference genome project, featuring Dr. Brian Davis, an assistant professor of genetics, graduate student Sam Stroupe, and collaborators from Texas Parks and Wildlife and the National Park Service.
In reference to the development of the bison reference genome, Dr. Brian Davis explained that reference genomes play a crucial role in identifying and understanding genes associated with various traits. This technology is versatile, being employed in tasks such as diagnosing health conditions and formulating targeted treatments.
The latest bison reference genome was crafted using advanced technology capable of constructing genomes from hybrids, animals possessing DNA from two distinct species. Specifically, the researchers utilized DNA from a bison-cow hybrid known as an F1, characterized by an even 50-50 distribution of DNA from its parental sources.
Typically uncommon, F1 hybrids resulting from the interbreeding of bison and cattle have been historically documented. Recent research, led by Derr and collaborators, revealed that a substantial number of bison herds in North America have descendants with hybrid ancestry—a finding unveiled last year.
In recounting the discovery process, Derr explained that Texas Parks and Wildlife informed the research team about an individual with a fully documented, first-generation F1 hybrid. This unique finding, encountered after 25 years of working with bison, provided the crucial material for the comprehensive genome development.
The process of constructing the updated bison genome involved sequencing the genomes of the F1 hybrid, the bison mother, and the domestic cattle father. By doing so, the researchers could discern and differentiate between the DNA specific to bison and the regions inherited from the cattle in the hybrid.
The well-established cattle genome served as a valuable reference point, facilitating the creation of the new high-resolution bison genome by guiding researchers through the process.
To demonstrate the efficacy of the newly developed genome, the team embarked on a mission to identify the gene mutation accountable for albinism in bison and to establish a genetic test capable of identifying carriers of this mutation.
This marks the initial instance where researchers have successfully identified the gene mutation responsible for a visible characteristic in bison.
Stroupe explained that the researchers were aware that albinism was a hereditary recessive trait but were uncertain about the specific gene responsible. To address this, they conducted DNA sequencing on albino bison and compared it with the DNA of bison with normal coloration. Through this analysis, they identified a mutation associated with albinism. This mutation adversely affects a crucial enzyme, causing it to malfunction and ultimately resulting in the absence of skin pigmentation.
The singular characteristics of albino bison
White bison hold sacred and spiritual importance for numerous North American Indigenous communities, with some viewing them as prophetic entities. The birth of a white bison, though not always indicative of albinism, is a cause for celebration in certain cultures. Despite recognizing this cultural significance, Derr is not advocating for the use of genetic testing to intentionally produce albino bison.
Derr expressed concern about the health of albino bison, noting that they typically face health challenges. These challenges include an increased susceptibility to skin cancers and the potential development of other health issues as they age.
Bison with albinism differ from those with white or tan coloring resulting from crossbreeding with white cattle, notably Charolais. Unlike true albinos, these bison lack the characteristic red eyes and pink nose. With the availability of a more precise bison genome, scientists can delve deeper into understanding the genetic composition of North America’s bison population.
Derr expressed enthusiasm about the development of the new reference genome and the discovery of the causative genetic mutation for bison. This development is seen as significant, as it paves the way for new discoveries and a deeper understanding of bison genetics. In essence, it represents a crucial advancement in the ongoing efforts for the conservation management of the United States’ national mammal.
- NEWSPAPER Price, C. & Texas A&M University. (2023, November 20). Researchers develop comprehensive genetic map for bison, discover gene responsible for albinism. Phys.org. [Phys.org]
- JOURNAL Stroupe, S., Martone, C., McCann, B. E., Juras, R., Kjöllerström, H., Raudsepp, T., Beard, D., Davis, B. W., & Derr, J. N. (2023). Chromosome-level reference genome for North American bison (Bison bison) and variant database aids in identifying albino mutation. G3: Genes, Genomes, Genetics, 13(10). [G3: Genes, Genomes, Genetics]