Genetic variability in the kappa‐casein gene in Sahiwal, Cholistani and Red Sindhi cattle breeds

Abstract

Polymorphism of kappa‐casein (κ‐CN) gene in three Bos indicus cattle breeds was investigated using a polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) technique. Only genotypes AA and AB were observed, and no BB, AE, BE, EE, AC or BC genotypes were detected in the three cattle breeds. In the Sahiwal, Cholistani and Red Sindhi breeds, the frequencies of the allele A were 0.69, 0.90 and 0.86, and the frequencies of the allele B were 0.31, 0.10 and 0.14, respectively. The Sahiwal breed was found to have a higher frequency of the AB genotype as compared to the Cholistani and Red Sindhi breeds. The frequency of the κ‐CN alleles noted in the three cattle breeds was similar to those observed in other cattle breeds of B. indicus origin.

The genotypic profile of milk proteins in Holstein cows raised in South of Brazil

“…The frequencies for A, B, and C alleles were calculated by direct counting. A chi-square test (χ²) was employed to see whether the population of animals used were in Hardy-Weinberg equilibrium to 0.05 significance value (P < 0.05) (Riaz et al 2012), by R program 4.1.2 (R Code Team, 2021). Thus, the following equation was used:…”

“…Milk quality as well as solids, such as fat and protein, are important to the dairy industry due to their influence on the production of dairy products, such as cheeses (Cecchinato et al 2015;Bittante et al 2013). In addition, the animal genetic background is an important source of variation in milk quality, thus, the study of the genetic variations in the milk protein composition has become essential for the selection of the animals (Riaz et al 2012). Within the milk protein, the kappa-casein I and II (κ-CNI and κ-CNII), α-s1-casein (α-s1-CN) and β-lactoglobulin (β-LG) are the most important protein variants and are present in greater proportion in milk (Visker et al 2010).…”

Molecular characterization of Kappa-casein and β-lactoglobulin genes in Anatolian Black cattle and Holstein breeds

“…Zootec., v.74, n.1, p.133-140, 2022Singh et al, 2015;Zhang et al, 2006). Casein contains around 75-80% of the total milk proteins (Azevedo et al, 2008;Bhat et al, 2016;Riaz et al, 2012). κ-CN is a single chain polypeptide that contains 196 amino acids with a molecular weight of 19.2 kDa and constitutes about 12% of the bovine casein.…”

“…β-lactoglobulin is the major whey protein of cattle milk and it is also present in many mammalian species, but it is absent in human milk (Crowther et al, 2016;Sawyer and Kontopidis 2000;Xiang et al, 2019). The bovine β-lactoglobulin gene is located at chromosome 11 and contains 7 exons and 6 introns with approximately 4.7kb (Riaz, 2013). Detected fifteen polymorphic variants of βlactoglobulin gene have two most frequent variants A and B.…”