Genetic Variants of Kappa Casein in Tunisian Native Goats
Main Article Content
Abstract
Introduction: The nutritional qualities of goat milk are affected by both environmental factors and genetic variations within casein genes. This study aims to assess the genetic polymorphism of the Kappa Casein (CSN3) gene in a goat population from Southeast Tunisia. This population is known for its exceptional resilience to harsh conditions, including limited feed and water scarcity.
Materials and methods: The PCR-RFLP was used to analyze the genomic DNA of 48 blood samples belonging to unrelated individuals from the Tunisian goat population for the CSN3 casein gene variability, at positions 166 and 448 bp.
Results: The analysis revealed a high prevalence of the GG genotype at position 166 and the TT genotype at position 448. Interestingly, the frequency of alleles from group I (A, B, E, F, H, J, and K) in the studied goat population of the present work is quite high; the alleles belonging to this group were known as associated with higher milk protein content. These findings suggest that these goats possess genetic traits that may improve milk protein production, which is crucial for ensuring the survival and well-being of their offspring.
Conclusion: The prevalence of alleles within the CSN3 gene, which is associated with high milk protein content, is a notable finding in this study. These genetic characteristics help mitigate the negative impacts of restricted feed and water on the growth and development of the offspring. The present study displays one of several adaptative features of this goat population which may highlight also the importance of these traits for sustainable goat breeding and milk quality improvement.
Article Details

This work is licensed under a Creative Commons Attribution 4.0 International License.
References
Nayik GA, Jagdale YD, Gaikwad SA, Devkatte AN, Dar AH, and Ansari MJ. Nutritional profile, processing, and potential products: A comparative review of goat milk. Dairy. 2022; 3(3): 622–647. DOI: 10.3390/dairy3030044
Rahmatalla S, Arends D, and Brockmann GA. Review: Genetic and protein variants of milk caseins in goats. Front Genet. 2022; 13: 995349. DOI: 10.3389/fgene.2022.995349
Campos MIF, de Souza Barbosa PP, Camargo LJ, Da Silva Pinto L, Mataribu B, Serrão C, et al. Characterization of goat whey proteins and their bioactivity and toxicity assay. Food Biosci. 2022; 46: 101591. DOI: 10.1016/j.fbio.2022.101591
ALKaisy QH, Al‐Saadi JS, AL‐Rikabi AKJ, Altemimi AB, Hesarinejad MA, and Abedelmaksoud TG. Exploring the health benefits and functional properties of goat milk proteins. Food Sci Nutr. 2023; 11(10): 5641–5656. DOI: 10.1002/fsn3.3531
Dagnachew BS, Thaller G, Lien S, and Ådnøy T. Casein SNP in Norwegian goats: Additive and dominance effects on milk composition and quality. Genet Sel Evol. 2011; 43(1): 31. DOI: 10.1186/1297-9686-43-31
Vacca GM, Dettori ML, Piras G, Manca F, Paschino P, and Pazzola M. Goat casein genotypes are associated with milk production traits in the Sarda breed. Anim Genet. 2014; 45(5): 723-731. DOI: 10.1111/age.12188
Zhang Y, Wang K, Liu J, Zhu H, Qu L, Chen H, et al. An 11-bp Indel polymorphism within the CSN1S1 gene is associated with milk performance and body measurement traits in Chinese goats. Animals. 2019; 9(12): 1114. DOI: 10.3390/ani9121114
Dettori ML, Pazzola M, Noce A, Landi V, and Vacca GM. Variations in casein genes are associated with milk protein and fat contents in Sarda goats (Capra hircus), with an important role of CSN1S2 for milk yield. Animals. 2023; 14(1) : 56. DOI: 10.3390/ani14010056
Meena AS, Kumar R, Misra SS, Kumar A, Kumari S, Malakar D, et al. Importance of genetic polymorphism of goat milk proteins on human nutrition and health: A review. BKAP. 2021; 36(3): 173-177. 10.18805/BKAP347
Chiatti F, Caroli A, Chessa S, Bolla P, and Pagnacco G. Relationships between goat к-casein (CSN3) polymorphism and milk composition. Proceedings of the Role of Biotechnology, Villa Gualino, Torino, Italy, 2005. p. 163–-164. Available at: http://www.fao.org/biotech/docs/chiatti.pdf
Chiatti F, Chessa S, Bolla P, Cigalino G, Caroli A, and Pagnacco G. Effect of к-casein polymorphism on milk composition in the Orobica goat. J Dairy Sci. 2007; 90(4): 1962-1966. DOI: 10.3168/jds.2006-508
Caravaca F, Carrizosa J, Urrutia B, Baena F, Jordana J, Amills M, et al. (2009). Short communication: Effect of ⍺s1-casein (CSN1S1) and к-casein (CSN3) genotypes on milk composition in Murciano-Granadina goats. J Dairy Sci. 92(6): 2960-2964. DOI: 10.3168/jds.2008-1510
Pasture Breeding Office (OEP). Tunis: Livestock and Pasture Office; c2024. Données sectorielles - effectifs du cheptel. Available at: http://www.oep.nat.tn/index.php/fr/donnees-sectorielles/40-effectif-s-du-cheptel
Nafti M, Khaldi Z, and Haddad B. Genetic relationships and structure among goat populations from southern Tunisia assessed using microsatellites. J New Sci. 2016; 27(5): 1488-1497. Available at: https://www.jnsciences.org/agri-biotech/35-volume-27/140-genetic-relationships-and-structure-among-goat-populations-from-southern-tunisia-assessed-using-microsatellites.html
National Observatory of Agriculture (Onagri). Precipitation: Annual average of cumulative precipitation observed over the period 1981-2010; Available at: https://onagrihome.files.wordpress.com/2022/06/note-de-synthese.pdf
Ammar H, Bodas R, Ben Younes M, and López S. Goat breeding systems in the south of Tunisia (Tataouine). Economic, social and environmental sustainability in sheep and goat production systems. Zaragoza: CIHEAM/FAO/CITADGA, 2011. http://om.ciheam.org/article.php?IDPDF=801516 p. 283-288.
Mohamed C, Dhaoui A, and Ben-Nasr J. Economics and profitability of goat breeding in the Maghreb region. Goat Science - Environment, Health and Economy. IntechOpen. 2023. DOI: 10.5772/intechopen.96357
Gaddour A, and Najari S. Pure breeds and crossed caprine genotypes effect in the oases of southern Tunisia. Afr J Agric Res. 2009; 4(11): 1203-1207. Available at: https://academicjournals.org/journal/AJAR/article-full-text-pdf/9D0352F37917
Sambrook J, Fritsch EF, and Maniatis T. Molecular cloning: A laboratory manual. 2nd ed. Cold Spring Harbor (NY): Cold Spring Harbor Laboratory Press; c1989.
Rousset F. GENEPOP'007: A complete re-implementation of the GENEPOP software for Windows and Linux. Mol Ecol Resour. 2008; 8: 103-106. DOI: 10.1111/j.1471-8286.2007.01931.x
Grosclaude F, and Martin P. Casein polymorphisms in the goat. 1997.
Hayes H, Petit E, Bouniol C, and Popescu P. Localization of the α-S2-casein gene (CASAS2) to the homoeologous cattle, sheep, and goat chromosomes 4 by in situ hybridization. Cytogenet Genome Res. 1993; 64(3-4): 281-285. DOI: 10.1159/000133593
Popescu P, Long S, Riggs PWJ, Schmutz S, Fries R, and Gallagher DS. Standardization of cattle karyotype nomenclature: report of the committee for the standardization of the cattle karyotype. Cytogenet Cell Genet. 1996; 74: 259-261. DOI: 10.1159/000134429
Yahyaoui MH, Coll A, Sanchez A, and Folch JM. Genetic polymorphism of the caprine kappa casein gene. J Dairy Res. 2001; 68(2): 209-216. DOI: 10.1017/S0022029901004733
Yahyaoui MH, Angiolillo A, Pilla F, Sanchez A, and Folch JM. Characterization and genotyping of the caprine κ-casein variants. J Dairy Sci. 2003; 86(8): 2715-2720. DOI:
3168/jds.S0022-0302(03)73867-3
Prinzenberg EM, Gutscher K, Chessa S, Caroli A, and Erhardt G. Caprine κ-casein (CSN3) polymorphism: new developments in molecular knowledge. J Dairy Sci. 2005; 88(4): 1490-1498. DOI: 10.3168/jds.S0022-0302(05)72817-4
Di Gerlando R, Tortorici L, Sardina MT, Monteleone G, Mastrangelo S, and Portolano B. Molecular characterisation of κ–casein gene in Girgentana dairy goat breed and identification of two new alleles. Ital J Anim Sci. 2015; 14(2): 3464. DOI: 10.4081/ijas.2015.3464
Darwish AM, Darwish HR, Ali NI, Abdel-Salam AM, Lethy HM, Mohamed IE, et al. Genetic variations of α-casein and K-casein genes associated with milk composition in goats. Small Rumin Res. 2023; 229: 107146. DOI:
1016/j.smallrumres.2023.107146
Susilorini TE, Furqon A, Septian WA, Wulandari D, and Suyadi S. Polymorphism of Kappa-Casein gene (CSN3| Alw44I) and its effect on milk yield and compositions in Indigenous Senduro goat. Adv Anim Vet Sci. 2022; 10(6): 1333-1338. DOI:
17582/journal.aavs/2022/10.6.1333.1338
Catota-Gómez LD, Parra-Bracamonte GM, Cienfuegos-Rivas EG, Hernández-Meléndez J, Sifuentes-Rincón AM, Martínez-González JC. Frequency and association of polymorphisms in CSN3 gene with milk yield and composition in Saanen goats. E y R A, 2017; 4(12): 411-417. DOI:
19136/era.a4n12.1165
Hill, R. J., & Wake, R. G. (1969). Amphiphile nature of κ-casein as the basis for its micelle stabilizing property. Nature, 221(5181), 635-639. DOI: https://doi.org/10.1038/221635a0
Ünal, H., & Kopuzlu, S. (2022). The relationships between κ-casein (CSN3) gene polymorphism and some performance traits in Simmental cattle. Arch Anim Breed, 65(1), 129-134. DOI: https://doi.org/10.5194/aab-65-129-2022