Now that we have established all our genetic terms and descriptions, we also need a general understanding of how the allele sequencing is predicted. This is fairly simple, as with the use of punnet squares, we can break down the phenotype to individual allele groups.
I will, very soon, go into depth on our earlier phenotype and its expressions, however, it is also important to establish how we go about doing that! I am still using the examples of "B" ("BB, Bb, bb") as in our Black Labrador, however for a moment, ignore our friend the yellow Lab. I have replaced him with a Chocolate Lab (red expression of black, note this is still eumelanin being expressed) who is phenotypically "bb". I will further explain this colour variation later on, I am merely using it as an example in my punnet square example.
The use of this punnet square is simply a visual aid and enables us to calculate the probabilities of particular alleles and their expressions. A Dominant/Recessive form is show above. (As we all know "BB" x "BB" = %100 "BB", I will not go into detail using squares for that figuration.)
Now is when our working out gets interesting. Let's say, instead of a "BB" completely dominant black Labrador, we somehow manage to breed a "Bb" to our "bb". Our resulting combination differs:
Without going into details of our two colours, it is apparent that our punnet squares are a very effective means of estimating offspring variations. (Keep in mind there are many other factors that do come into play.) There - a simple method of mastering dog genetics! If only it was all that simple.
Now, onto our genotypes and phenotypes! We will, of course, being with Black.
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