Fleckvieh haplotype 2 / FH2 (SLC2A2-related) - Cattle

Fleckvieh haplotype 2 (FH2)

This DNA test detects the SLC2A2 variant c.771_778delTTGAAAAGinsCATC associated with Fleckvieh haplotype 2, also known as FH2. The condition has been described in Fleckvieh- and Brown Swiss-related populations and is linked to growth retardation, disturbed glucose handling and serious liver and kidney problems in affected calves.

SLC2A2 encodes GLUT2, a transporter important for glucose transport in tissues including liver, kidney, pancreas and intestine. When both gene copies carry the tested variant, the genotype is consistent with the FH2 disease presentation.

Inheritance and meaning

FH2 is inherited as an autosomal recessive trait. Carriers have one copy of the tested variant and can pass it on without showing the FH2 disease presentation themselves. Calves with two copies have an unfavourable genetic combination.

Practical value of this test

• Breeding planning: identify carriers before mating or insemination.
• Risk reduction: avoid combinations where both parents can pass on the same FH2 variant.
• Herd value: keep valuable carrier lines in use by pairing them with clear animals.