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Miniature-Cattle.com breeding miniature cattle 12 Things to Understand about Genetic Mutations in Cattle
see also: DNA tests; genetic traits, genetic diseases
see also: Sire Testing; what to check before collecting a bull
see also: Bull stats; information needed for selling frozen semen
see also: Biosecurity; closed herds, quarantine
see also: Herd Health; infectious diseases, testing, vaccination, management, prevention
see also: Chondrodysplasia; miniature cattle and dwarfism
see also: Breeds of Miniature Cattle in North America

 

GENETIC MUTATIONS
12 interesting facts about DNA

  1. Genetic scientists will not say some of the things I list in this small article ... because scientifically, not all of these claims are absolute reproducable facts... these are perhaps more like, reliable "rules" that nature follows, but with that tiny bit of wiggle room for one case to come along and strike lightening twice, etc. This list of "facts" is intended to help set a foundation understanding about how different genetic mutations (the genotype) typically occur and function to produce similar (nearly identical) effects on the animal (the phenotype). This list of "facts" also demonstrates how mutations over decades and centuries provide proof of the relationship between breeds and provides reasonable evidence of their origins, history and development.

  2. Genetic diseases in cattle are tissue specific viz; skeletal, central nervous system, blood, skin /hair, muscle or ophthalmic.

  3. Genetic disorders, and genetic diseases are caused by inherited abnormalities, novel spontaneous mutations or damage to genes or chromosomes.

  4. In 2016, there were 130 Mendelian traits with known causal mutations in 117 cattle genes.

  5. Genetic mutations do not all cause disorders or disease. Mutations are very common, and exist (probably numbering in the 100s) in most all living animals. The possibiliy of how many mutations could occur in any one population over time, is practically infinite.

  6. On the opposite end of the spectrum, is the probability of the exact same mutation happening more than once in the same breed or population of animals, over time; which is close to nil. The possibility of that occuring might be comparable to finding 2 unrelated people with identical fingerprints.

  7. For all intents & purposes, if the exact same genetic mutation is found in 2 different animals of the same species, they are related. Having the same exact mutation indicates they both trace back to to the same ancestor that the mutation occurred in, and was passed down from. That is why particular genetic mutations are found in breeds that share history, or in specific breeds, or in certain bloodlines, depending upon how long ago the mutation occurred and has spread.

  8. Many genetic mutations are undesirable. Most mutations probably cause spontaneous abortions or do not survive into breeding age animals. Some mutations are surviveable over the generations. Some abnormalities are beneficial. These mutations are essentially how populations survive changes, and evolution occurs.

  9. Some genetic conditions are markers (closely linked) for economically important or desirable traits. For example, desirable hair for club calves may result from alleles located close on the gene to the PHA disease mutation, which initially led to PHA's increase among Maine Anjou club calf cattle.

  10. There can be a number of different mutations (genotype) that result (phenotype) in the same disease. For example, there are several mutations that cause bulldog chondrodysplasia dwarfism in cattle.

  11. Each different mutation requires its own particular DNA test to identify it (even if the condition they cause may be identical).

  12. Genomic technology is ever-evolving. Before making any financial decisions, such as implementing DNA testing in your cattle program or even choosing a breed, check for the latest updates on research, lab-testing, products and news. If you are not currently testing it may be prudent to collect DNA samples (e.g. tail hair) on important animals in your herd (e.g. herd bulls) and store them for potential future research.

go home little cow
go home little cow

publisher: Vintage Press
published online: March 2019
author: Donna Grace