Breeding. Mutations

Roman

Geneticist
Staff member
#1
Well... We learned about how unicorns are breeding, learned about the important chromosome crossingover operation, which provides genetic diversity. Let's continue. If you think about it, it becomes clear that you can not reach the diversity just by crossing. After all, if we have a limited number of unicorns of the zero generation (GEN-0), then all their descendants will carry only their genes. There will be some varieties, but if in the original population did not turn out any particularly beautiful wings, they will take absolutely no place.

In the case comes the second operation on the genes, which is applied after determining the genotype of the new unicorn on the basis of a crossingover of chromosomes of parents — a mutation. A mutation is not something harmful, not when a unicorn grows a second horn or something like that (this term usually has such connotation in popular culture). A mutation is just a change in genetic information under the influence of some random external factors. All genes always mutate with some frequency, and some of them are fixed in generations, because they give their carriers some kind of benefit. But most often, of course, mutations are malevolent. So unicorns have the same thing.

Mutations when inheriting genetic information from unicorns have two aspects:
  • Frequency of mutations.
  • Distribution of types of mutations.
Let's consider both.

The frequency of mutations is the probability with which each gene can undergo a mutation. The frequency of mutations depends on the «goodness» of the unicorn approximately according to the logistic law, starting from 15 % for the most inferior unicorns to 40 % for the best ones. This frequency means this. When genotyping a new unicorn, for each gene, bones range from 0 to 100 %, and if the dropped value is less than the mutation frequency, then a mutation occurs for this gene. For this gene, a random allele is taken and one of four types of mutations is performed:
  • Very severe deterioration — 40 % of the mutations.
  • Deterioration — 30 % of the mutations.
  • Improvement — 20 % of the mutations.
  • The «transfer» of the value — 10 % of the mutations.
The transfer of the value of the gene allele is the choice of a random new value within the range of the gene domain for the dominant unicorn race. But deterioration and improvement are the shift in the boundaries of the area of the gene definition down or up. Down 50 % is a very severe deterioration, down 25 % is a simple deterioration, up 25 % is an improvement.

Something like that. Do not be surprised that if you pair two unicorns with legendary body parts and high physical characteristics, then the result is a uniform bastard. This is a payment for high characteristics. The better the unicorn is, the more difficult is it for him to improve or even simply transfer its genes to the next generation.