Genetic Visions-ST

Arachnomelia is a simple lethal recessive gene defect in cattle. Affected animals are born with elongated limbs and facial deformities. There are two versions of this defect originating in Brown Swiss and Simmental cattle.

Arachnomelia is a simple lethal recessive gene defect in cattle. Affected animals are born with elongated limbs and facial deformities. There are two versions of this defect originating in Brown Swiss and Simmental cattle.

There are two genes associated with BCN that we test for, A1 and A2, and three possible genotypes: A1/A1, A1/A2, and A2/A2. There has been a lot of interest in this trait over the last decade allowing for increased marketing opportunities for A2/A2 milk.

The colored breeds are more likely to have the A2 gene and A1 is more evenly distributed in Holsteins, but selective breeding may be changing this distribution.

BLAD is a simple lethal recessive gene defect found in the Holstein Breed. A mutation in the CD18 gene causes a malfunction. A sticky substance normally found on the surface of leukocytes, which is essential to its ability to function, is reduced in animal

There are two genes that have been associated with Beta-Lactoglobulin. When a sample is submitted for analysis, the results will be reported AA, AB, or BB. In the case of BLG, AA is considered the most favorable, AB is intermediate, and BB is the least favorable.

In general, animals with beta·lactoglobulin genotype of AA had increased transmitting abilities for milk yield and protein yield but decreased transmitting abilities for fat.

Brachyspina is a simple lethal recessive defect in Holstein cattle. It is characterized by stillbirth, reduced body weight, shortening of the spine, and long thin limbs.

Calpain 316 and 530 are genes related to meat tenderness. Research at USDA, Meat Animal Research Center, Clay Center, NE has shown that the meat tenderization process is impacted by mutations within the naturally occurring gene that produces the enzyme u-calpain. The Warner-Bratzler shear force test is used to measure meat tenderness.

Animals that inherit the C allele at position 316 and/or the G allele at position 530 require less shear force to cut test samples, denoting increased tenderness. We test and report results for both 316 and 530 when ordered.

Citrullinemia is a simple lethal recessive gene defect. Animals inheriting two copies of the defective gene die within 5 days of birth due to their inability to eliminate ammonia.

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The first expression of Dominant Red was in HOCANF000003541221. Neither of her parents carried the recessive red gene that was the only known cause of red coat color in Holsteins at that time. In 2013, the causative gene mutation for this trait was found, and Genetic Visions developed a test shortly thereafter.

Dominant Red has the benefit of superseding the traditional MC1R when present and one or two copies of the gene will be expressed with a red phenotype. DR and MC1R are located in different parts of the genome and are passed on independently. Breeders now have more options to incorporate red animals into their Holstein herds, and the true origin of the color in each animal can be determined to better assist in mating decisions.

DUMPS is a simple lethal recessive gene defect that causes a failure in the synthesis of DNA. Embryos inheriting two copies of the gene defect are lost around day 40 of pregnancy.

Factor XI is a simple lethal recessive gene defect in which a plasma protein that facilitates the formation of blood clots is deficient. Affected animals have a form of hemophilia with increased bleeding from wounds and potential spontaneous hemorrhaging. Their life expectancy is decreased, but they have the potential to live to maturity and procreate.

Freemartinism is one of the most extreme forms of sexual abnormality in cattle. This condition is found in fraternal twins in cattle where an imperfect, masculinized, sterile female twin calf is born with a male. Without a simple means to test young animals for the freemartin condition, many producers discard a heifer twin to a bull shortly after birth.

This DNA based test identifies the presence of the Y chromosome. Since females are XX and males are XY, a positive Y chromosome test result for a heifer born twin to a bull indicates the freemartin condition. The number of cells containing the Y chromosome will be greatest at birth, but it is a lifelong condition that can be tested at any point.

Genetic Visions-ST™ freemartin test requires that a minimum of 2 ml of blood be placed in a tube containing an anticoagulant, i.e. EDTA (purple top). The samples do not need to be refrigerated during shipment and can be sent in a routine mailer. The only requirement is that the shipment arrives intact, so we suggest a small box with padding (paper towels, bubble wrap, etc.) to protect the sample.

Purple top tubes for blood collection can be obtained from your local vet clinic.

There is a causative mutation in the FMO3 gene of some cattle that causes fishy off-flavor milk. This defect was first seen in Swedish Red and White cattle and can now be found in Ayrshires as well. Affected animals have bodily fluids characterized by a distinct, unpleasant smell of rotting fish.

Though not a lethal recessive, this is a highly unfavorable attribute.

Cholesterol Deficiency is a lethal recessive defect in Holstein cattle. Affected animals lack cholesterol in their cells. Without fat, the body slowly weakens and dies. Most affected animals die between 1 to 5 months, but some have lived as long as 2 years. This long, yet futile lifespan can make HCD a very costly disease both financially and emotionally. Heterozygous carriers of the disease show lower levels of cholesterol in the blood than normal animals.

Kappa-Casein is one of four non-whey proteins and has been associated with increased cheese protein yield and percentage. Genetic Visions tests for three forms of the kappa-casein gene: A, B, and E. The B gene has been associated with an increase in milk, protein, and cheese yield. The E gene is the least favorable and linked to the A gene.

Animals carry one of three gene combinations from each parent. Studies from around the world have shown that the BB genotype is the most favorable in terms of protein and cheese yield. AB is somewhate intermediate and AA is the least favorable.

Potential gene combinations follow in order from most to least favorable. They are listed with the AB/AE form and combined form. Since the E gene is only associated with the A gene, the combined form replaces an A in the first set with any E’s from the second set

BB/AA (BB)
AB/AA (AB)
AB/AE (BE)
AA/AA (AA)
AA/AE (AE)
AA/EE (EE)

The MC1R Red Factor offered by Genetic Visions tests three gene variants that affect the coat color of both beef and dairy cattle. Black (ED) is dominant. The wild type (E+) can have a phenotype of many shades from red to brown and is usually homozygous in the colored breeds (Jersey, Guernsey, etc.).

Red (e) is recessive and will only be expressed if two copies are present.

The possible gene combinations and phenotypic expression follow:

ED/ED (homozygous black)
ED/E+ (not a true black)
ED/e (red carrier)
E+/E+ (homozygous wild-type with red to brown coloring depending on breed)
E+/e (black/red, usually darkening with age))
e/e (homozygous red))

SDM is a simple lethal recessive gene defect in Brown Swiss cattle that is symptomatic from birth. Affected animals are never able stand and die within a week.

SMA is a simple lethal recessive gene defect causing a wasting disease in Brown Swiss cattle with symptoms starting in the first few weeks of life. It generally starts in the rear legs and progresses forward.

Once it affects the major organs and the calf is no longer able to stand, death usually occurs within a couple of days from pneumonia. Affected animals usually die within 6 to 8 weeks of age.