Assessment of Genetic Variability in Prolactin Gene and Its Impact on Milk Composition in Bos indicus Cattle

Polymorphism of SNP g.8398A>G at prolactin gene and its effect on Indonesian Holstein dairy cow’s milk performance and reproductive traits

“…Prolactin is a key regulator of milk production, mammary gland development, and milk protein gene expression (Shah et al, 2021). An association between genotype variations in the Prolactin gene and milk composting in Bos indicus has been discovered by Agrawal et al (2020). The finding of this study was similar to the previous study in crossbreed cattle in India, which found the RR genotype is significantly associated with protein and fat; unfortunately, the genotype in Jersey cows was not associated with milk quality (Shah et al, 2021).…”

“…GG, or in some other studies called AA, which was not digested by the RsaI enzyme (0.60), AG (0.37) and AA (0.03). While Frieswal cattle (Bukhari et al, 2013) and Bos indicus in India (Agrawal et al, 2020) found dominant heterozygous genotype AG (or AB in another study) of 0.629 and 0.72, respectively. The frequency of GG, GA, and AA genotypes in the intron 3 and intron 4 regions were 0.76, 0.23, and 0.12; respectively, in Chinese Holstein cow (Dong et al, 2013).…”

“…The prolactin (PRL) gene is a candidate gene that affects milk traits (Brym et al, 2005;Agrawal et al, 2020;Shah et al, 2021). Prolactin is a hormone with a polypeptide structure which is about 10 kb in size and composed of 5 exons and 4 introns, it has been identified to be located on chromosome 23 near the quantitative trait loci in the bovine genome (Hallerman, 1988;Ozdemir, 2020).…”

“…Polymorphism in several regions of the prolactin gene has been reported, i.e. on exon 3 in Turkish native cattle breeds (Unal et al, 2015), Frieswal cow (Bukhari et al, 2013), Bos indicus in India (Agrawal et al, 2020), American Swiss cattle in Mexico (Alfonso et al, 2012), Gir and Kankrej cattle (Patel and Chauhan, 2017), on exon 4 at Holstein Friesian heifer in Turkey (Yasemin et al, 2017), on Exon 3 and 4 at Holstein cow in Turkey (Ozdemir, 2020), on partial intron 3 and 4 at Chinese Holstein cows (Dong et al, 2013), however, information on the identification of polymorphism of the exon 4 prolactin gene in Indonesian FH dairy cows is still rare.…”

“…Genetic polymorphism studies revealed a significant association between the genotype of the prolactin gene with milk traits in cattle (Brym et al, 2005;Patel and Chauhan, 2017;Agrawal et al, 2020;Hani et al, 2021;Shah et al, 2021), reproductive in cattle (Gayari et al, 2020;Pytlewski et al, 2020). The prolactin gene has been observed for the milk trait in buffaloes (El-Magd et al, 2015;Nadeem and Maryam, 2016), milk trait in sheep (Gras et al, 2016;Ozmen and Kul, 2016;Padilla et al, 2018), a reproductive trait in Awassi ewes (Al-Thuwaini, 2021), also reproductive trait in Alabio and Mojosari ducks (Damayanti et al, 2022).…”