Population Genetic Analysis Of Prolactin (PRL) Gene Polymorphisms In  Bushuev Breed Cattle In Uzbekistan

Authors

  • B Akhmadaliev Animal Genetics Laboratory, Institute of Genetics and Plant Experimental Biology, Academy of Sciences of the Republic of Uzbekistan, Kibray Dis trict, Tashkent Region, Uzbekistan
  • B Adilov Animal Genetics Laboratory, Institute of Genetics and Plant Experimental Biology, Academy of Sciences of the Republic of Uzbekistan, Kibray Dis trict, Tashkent Region, Uzbekistan
  • A Sherimbetov Animal Genetics Laboratory, Institute of Genetics and Plant Experimental Biology, Academy of Sciences of the Republic of Uzbekistan, Kibray Dis trict, Tashkent Region, Uzbekistan
  • B Abdikarimov Animal Genetics Laboratory, Institute of Genetics and Plant Experimental Biology, Academy of Sciences of the Republic of Uzbekistan, Kibray Dis trict, Tashkent Region, Uzbekistan
  • D Ruzmetov Animal Genetics Laboratory, Institute of Genetics and Plant Experimental Biology, Academy of Sciences of the Republic of Uzbekistan, Kibray Dis trict, Tashkent Region, Uzbekistan
  • B Abduvaliev Animal Genetics Laboratory, Institute of Genetics and Plant Experimental Biology, Academy of Sciences of the Republic of Uzbekistan, Kibray Dis trict, Tashkent Region, Uzbekistan
  • B Gulomov Animal Genetics Laboratory, Institute of Genetics and Plant Experimental Biology, Academy of Sciences of the Republic of Uzbekistan, Kibray Dis trict, Tashkent Region, Uzbekistan

DOI:

https://doi.org/10.48165/ijapm.2026.42.SI.16

Keywords:

Prolactin (PRL) gene; SNP polymorphism; Bushuev cattle breed

Abstract

This study investigated genetic variability in the prolactin (PRL) gene  (g.8398A>G) and its association with milk production traits in the Bushuev  cattle population of Uzbekistan. A total of 96 lactating cows from Tashkent and  Syrdarya regions were genotyped using allele-specific real-time PCR. Genotype  frequencies were 0.250 (AA), 0.542 (AG), and 0.208 (GG), with corresponding  allele frequencies of 0.521 (A) and 0.479 (G). The population showed moderate  genetic diversity, with observed heterozygosity (Ho = 0.542) slightly exceeding  expected heterozygosity (He = 0.500), Nei’s genetic diversity index (H = 0.500),  and a negative fixation index (FIS = −0.084), indicating an excess of heterozygotes  and absence of inbreeding. The population conformed to Hardy–Weinberg  equilibrium (χ² = 0.669, p > 0.05), suggesting its genetic stability. Association  analysis revealed a significant effect of PRL genotypes on milk production traits  (p < 0.001). The heterozygous AG genotype exhibited the highest milk yield  (5489.3 ± 30.5 kg), while the AA genotype showed significantly higher milk fat  (4.72 ± 0.05%) and protein (3.97 ± 0.06%) contents. The GG genotype displayed  intermediate performance for milk yield and lower compositional traits. These  results indicate a clear genotype-dependent trade-off between milk yield and  quality traits, suggesting possible heterozygote advantage at the PRL locus. Overall, the findings demonstrate that the g.8398A>G polymorphism of the PRL  gene is an informative genetic marker influencing economically important dairy  traits. The study highlights the potential application of this marker in breeding  programs aimed at improving milk productivity while maintaining desirable  milk composition in Bushuev cattle. Funding: Support was provided by the Academy of Sciences of the Republic  of Uzbekistan in the program of “Genotyping of genes responsible for milk  productivity and quality in cattle breeds”.

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Published

2026-06-01

Issue

Vol. 42 No. special Issue (2026): Indian Journal of Animal Production and Management (Apr-Jun)

Section

Research Article

How to Cite

Population Genetic Analysis Of Prolactin (PRL) Gene Polymorphisms In  Bushuev Breed Cattle In Uzbekistan. (2026). Indian Journal of Animal Production and Management, 42(special Issue), 117-123. https://doi.org/10.48165/ijapm.2026.42.SI.16