Whenever I'm asked about my work, people are amazed and can not understand the fact that a study of flies (plus the fact that they come to mind the black flies that haunt the poop). However, one does not use a lot of flies because you are interested in these insects (unless you're an entomologist), but rather because they are an excellent model for understanding how genes work, and as we have seen, the molecular mechanisms involved in how genes are basically the same for all animals on this planet (Is the reason this?, very simple, evolution).
If some do not know this little bug, looks like this:
His real name is Drosophila melanogaster, this is an insect of the order Diptera, an order which also includes mosquitoes and flies. Its common name is "fruit fly" or "fruit flies" as their main food in the wild are decaying fruit.
Its life cycle is that of a holometabolous insect, this means that after the adults lay eggs, they hatch into larvae, which are aimed to feed. Then these larvae transform into pupae, which emerge from the imago (adult) whose main goal is reproduction. This complete cycle is quite fast, a little over 2 weeks, which is the first major advantage of Drosophila as an experimental model, and you can do and get crosses generations in a reasonably short time.
At the genetic level, we find another major advantage of Drosophila , a completely sequenced genome and 4 pairs of chromosomes, one pair of sex (X and Y) and 3 pairs of autosomes, of which only the first 2 are relevant to geneticists, since the fourth chromosome is very small and not useful for transgenesis. However, there is the number of chromosomes in itself a great advantage (although it is much better than using an animal with dozens of them), but the existence of "chromosomes rocker", a powerful tool that offers this model.
rocker chromosomes have several features, one does not recombine during meiosis with their counterparts, so, if you have an animal heterozygous for a rocker, never mix genes across generations, even better, if a fly is homozygous for chromosomes rocker, will never develop, because, in general, these chromosomes contain lethal recessive genes, which are homozygous in the animal's death in such early stages of development as the embryo. Also, if the animal is heterozygous for the rocker (containing the gene of interest in its counterpart), is easily identifiable by their phenotype, as these chromosomes containing dominant markers, such as curved wings (a swing of the second chromosome), clipped wings (a swing of the third chromosome), etc. In this way, you only need to use a magnifying glass to know if the fly in question is homozygous for our gene of interest or heterozygous.
These are the main advantages has Drosophila genetics in thick, which allow you to cross and get a simple recombinant and effectively. However, the true fame of this animal are powerful molecular tools it has, but we will leave that for later. For now, geneticists believe me that these flies are a real goose that lays golden eggs.
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