Double Merle in Border Collis: Genetic and health implications
DOI:
https://doi.org/10.31533/pubvet.v19n03e1743Keywords:
Allele, phenotype, genetic, coat, deafnessAbstract
Currently, the growing demand for aesthetic characteristics in the pet market has generated a significant increase in the number of pets in the country, as indicated by several studies. One of the most sought after and desired coat patterns is the Merle pattern, characterized by a coloration that resembles marble, resulting from the action of the M (Merle) gene. This pattern is observed in several dog breeds, giving them a unique and attractive appearance. However, it is essential to understand that, in addition to aesthetics, the genetics behind this coat can have implications for the health of animals. This study aims to conduct an in-depth review of the influence of the Merle gene and the pathologies associated with it, in addition to comparing these conditions with other genetic anomalies related to dog coats. The Merle gene, responsible for the distinctive appearance, can be advantageous from a commercial and visual point of view, but dogs carrying this gene are more predisposed to hearing deficiencies, such as deafness, when compared to other dogs of the same breed, but with different coat patterns. This condition is associated with a range of health problems, including deafness, blindness, sterility and other physical anomalies that can be serious and even incompatible with life. These pathologies are a consequence of the accumulation of copies of the Merle gene, which makes it essential that breeders and owners are aware of the risks involved in breeding dogs with this coat pattern. In view of this, it is essential that veterinary professionals provide adequate guidance on the risks associated with breeding dogs with Merle coats, promoting the education of owners and breeders. Raising awareness of the consequences of irresponsible breeding practices is crucial to maintaining the health of animals and ensuring their well-being, preventing the spread of harmful genetic conditions. Thus, the responsibility for commercial breeding of the species falls on the veterinarian, who must act ethically and in an informed manner, aiming for a balance between the aesthetics and health of the dogs.
References
ABINPET. (2019). Informações gerais do setor pet. Informações Gerais Do Setor Pet.
ABINPET. (2022). Caderno especial Abinpet-Associação Brasileira da Indústria de Produtos para Animais de Estimação. Agro Analysis, 35(1), 35–40.
Bertipaglia, T. S., & Gomes, F. J. (2010). Melhoramento genético de cães (pp. 42–43).
Clark, L. A., Wahl, J. M., Rees, C. A., & Murphy, K. E. (2006). Retrotransposon insertion in SILV is responsible for Merle patterning of the domestic dog. Proceedings of the National Academy of Sciences of the United States of America, 103(5), 1376–1381. https://doi.org/10.1073/pnas.0506940103.
Comito, B., Knowles, K. E., & Strain, G. M. (2012). Congenital deafness in Jack Russell terriers: Prevalence and association with phenotype. Veterinary Journal, 193(2), 404–407. https://doi.org/10.1016/j.tvjl.2012.02.018.
Esteves, M. C. B. N., Dell’Aringa, A. H. B., Arruda, G. V., Dell’Aringa, A. R., & Nardi, J. C. (2009). Estudo das latências das ondas dos potenciais auditivos de tronco encefálico em indivíduos normo-ouvintes. Brazilian Journal of Otorhinolaryngology, 75(3), 420–425. https://doi.org/10.1590/S1808-86942009000300018.
Langevin, M., Synkova, H., Jancuskova, T., & Pekova, S. (2018). Merle phenotypes in dogs – SILV SINE insertions from Mc to Mh. PLoS ONE, 13(9), 1–20. https://doi.org/10.1371/journal.pone.0198536.
Mangolin, L. F., Ferreira, N. F., & Caminhas, M. M. T. (2020). Efeitos pleiotrópicos do gene Merle em cães: Revisão de literatura. Nucleus Animalium, 12(2). https://doi.org/10.3738/21751463.3779.
Meyers-Wallen, V. N. (2003). Ethics and genetic selection in purebred dogs. Reproduction in Domestic Animals, 38(1), 73–76. https://doi.org/10.1046/j.1439-0531.2003.00384.x.
Murphy, S. C., Evans, J. M., Tsai, K. L., & Clark, L. A. (2018). Length variations within the Merle retrotransposon of canine PMEL: Correlating genotype with phenotype. Mobile DNA, 9(1), 1–11. https://doi.org/10.1186/s13100-018-0131-6.
Otto, P. G. (2012). Genética básica para veterinária. Roca.
Pelles, Z., Gáspárdy, A., Zöldág, L., Lénárt, X., Ninausz, N., Varga, L., & Zenke, P. (2019). Merle allele variations in the mudi dog breed and their effects on phenotypes. Acta Veterinaria Hungarica, 67(2), 159–173. https://doi.org/10.1556/004.2019.018.
Platt, S. R., Freeman, J., Di Stefani, A., Wieczorek, L., & Henley, W. (2006). Prevalence of unilateral and bilateral deafness in border collies and association with phenotype. Journal of Veterinary Internal Medicine, 20(6), 1355–1362. https://doi.org/10.1892/0891-6640(2006)20,
Rooney, N. J. (2009). The welfare of pedigree dogs: Cause for concern. Journal of Veterinary Behavior: Clinical Applications and Research, 4(5), 180–186. https://doi.org/10.1016/j.jveb.2009.06.002.
Sans, E. C. O., Rüncos, L. H. E., Soriano, V. S., Schnaider, M. A., & Molento, C. F. M. (2018). Consequências da seleção artificial para o bem-estar animal. Revista Acadêmica Ciência Animal, 16. https://doi.org/10.7213/1981-4178.2018.161110.
Sommerlad, S., McRae, A. F., McDonald, B., Johnstone, I., Cuttell, L., Seddon, J. M., & O’Leary, C. A. (2010). Congenital sensorineural deafness in Australian stumpy-tail cattle dogs is an autosomal recessive trait that maps to CFA10. PLoS ONE, 5(10), 1–9. https://doi.org/10.1371/journal.pone.0013364.
Soriano, V. S. (2014). Seleção artificial e o bem-estar de cães. SB Rural.
Souza, C. C., Sacco, S. R., & Zappa, V. (2013). Distúrbios do equilíbrio ácido-básico revisão de literatura. Garça.
Stefanello, C. R. (2017). Estudo da via auditiva em cães beagles por meio de potenciais auditivos de tronco encefálico. Universidade Federal do Rio Grande do Sul.
Strain, G. M. (1999). Congenital deafness and its recognition. The Veterinary Clinics of North America. Small Animal Practice, 29(4). https://doi.org/10.1016/S0195-5616(99)50079-X
Strain, G. M. (2012). Canine deafness. Veterinary Clinics of North America - Small Animal Practice, 42(6). https://doi.org/10.1016/j.cvsm.2012.08.010
Strain, G. M. (2015). The genetics of deafness in domestic animals. Frontiers in Veterinary Science, 2(SEP), 1–20. https://doi.org/10.3389/fvets.2015.00029
Strain, G. M., Clark, L. A., Wahl, J. M., Turner, A. E., & Murphy, K. E. (2009). Prevalence of deafness in dogs heterozygous or homozygous for the Merle allele. Journal of Veterinary Internal Medicine, 23(2), 282–286. https://doi.org/10.1111/j.1939-1676.2008.0257.x.
Varga, L., Lénárt, X., Zenke, P., Orbán, L., Hudák, P., Ninausz, N., Pelles, Z., & Szőke, A. (2020). Being Merle: The molecular genetic background of the canine Merle mutation. In Genes (Vol. 11, Issue 6, pp. 1–15). https://doi.org/10.3390/genes11060660.
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