Associations among beta-lactoglobulin genotypes and some production traits in sheep: A systematic review and meta-analysis

Researchers have found contradictory evidence for the association between beta-Lactoglobulin (beta lg) polymorphism and certain production traits in sheep. The aim of the study is to explore the use of meta-analysis using different genetic models in relations to beta lg polymorphism in sheep for the purpose of investigating the association among beta lg genes and certain production traits, such as total milk yield, fat, protein, casein and lactose content. As a result of the analysis, the association between beta lg genotypes, protein and casein content was determined to be statistically significant (p<0.05). It was found out that the mean value was superior in favor of AA genotype for total milk yield, AB genotype for protein content and casein content especially in dairy subgroup. However, the association among beta lg genotypes and other yield properties was determined to be insignificant (p>0.05).