Water buffaloes (Bubalus bubalis) only have A2A2 genotype for beta-casein.

Area of Science:

• Animal genetics
• Dairy science
• Food science

Background:

• Beta-casein protein exists in A1 and A2 variants, with A1 linked to digestive discomfort.
• A2 milk, containing only beta-casein A2, is an alternative for easier digestion.
• Marker-assisted selection in cattle aims to increase A2A2 genotype frequency for A2 milk production.

Purpose of the Study:

• To investigate beta-casein A1 and A2 allele frequencies in buffaloes.
• To determine if buffaloes possess the beta-casein A1 allele.

Main Methods:

• Genotyping of 657 buffaloes across four breeds.
• Analysis of beta-casein gene alleles and genotypes.

Main Results:

• All genotyped buffaloes (n=657) exhibited the A2A2 genotype.
• The beta-casein A1 allele was not detected in any of the studied buffalo breeds.
• Buffalo milk inherently contains only beta-casein A2.

Conclusions:

• Buffaloes naturally produce only A2 beta-casein.
• All buffalo milk and derived products are naturally A2, offering a digestible alternative.
• This finding enhances the market value of buffalo milk products.