Genome-Wide Association Studies for Lactation Performance in Buffaloes.

Area of Science:

• Animal Genetics
• Dairy Science
• Genomics

Background:

• Buffaloes are vital genetic resources for dairy production, yet lactation performance improvements have lagged.
• Advancements in sequencing and genome-wide association studies (GWAS) offer new avenues for breeding superior buffalo.
• Limited genetic gains in buffalo lactation highlight the need for molecular-assisted breeding.

Purpose of the Study:

• To identify candidate genes associated with milk production traits in water buffalo using integrated genomic analysis.
• To provide a genetic basis for enhancing milk yield, protein, and fat content in buffalo populations.
• To leverage high-quality genome assembly and sequencing data for marker-assisted selection in buffalo breeding.

Main Methods:

• Integrated analysis of genomic sequencing data from 120 water buffalo.
• Utilized the UOA_WB_1 water buffalo genome assembly.
• Correlated genomic data with milk production traits: 305-day milk yield (MY), peak milk yield (PM), total protein yield (PY), protein percentage (PP), fat percentage (FP), and total milk fat yield (FY).

Main Results:

• Identified 56 significant single nucleotide polymorphisms (SNPs).
• Selected 54 candidate genes based on significant SNPs.
• Candidate genes were significantly enriched in key lactation-related pathways: cAMP signaling (ABCC4), TGF-β signaling (LEFTY2), Wnt signaling (CAMK2D), and metabolic pathways (DGAT1).

Conclusions:

• Identified specific candidate genes (ABCC4, LEFTY2, CAMK2D, DGAT1) associated with milk production traits.
• These genes offer a strong theoretical foundation for molecular breeding programs in buffalo.
• The study paves the way for targeted genetic improvement of milk production in dairy buffaloes.