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Reading assignment EssayThe common house mouse, Mus musculus, is a model being for human distempers. As such, it has been recently utilized in QTL mapping to see which genes may contribute disproportionately to disease states. Unfortunately, because of its high rate of inbreeding and bottleneck exit when it was first developed as a model organism, it displays a high level of linkage disequilibrium such that QTLs can span 20-40 cM, containing hundreds of genes. This is a problem on two levels One, while this resolution is great relative to the double crossovers of Morgans flies, it leaves much to be desiredin terms of quickly discovering traits that contribute to disease states. Two, using inbred lines such as mouse decreases verisimilitudewere trying to see how diseases work in humans, we should use animals with same genetic variance as humans. This is especially relevant because mice colonized the population with humans, and as such may show similar patterns of gene evoluti on and population structure. These authors found that QTL maps can be made to the resolution of 1 cM (about 100 kB in M. musculus) by using the haywire conspecifics of these lab mice. In doing so,they also found that ferine mice have much lower rates of LD, comparable to humans. They do show a lot of homozygosity, which the authors attribute to some inbreeding and previous bottlenecks. The authors suggest that using wild mice to develop finer mapping resolution for QTLs, especially because they can use the same SNPs that they use for laboratory mice. That is to say, we can use the same tools available to us in lab mice on wild mice for experiments more relevant to populations of humans, as opposed to individuals. Questions 1) Wild mice have a lot of homozygosity.Would wild mouse populations (new world field mice, etc. ) show less homozygosity, and can we use them in these experiments when homozygosity somehow impedes the resolution of the mapping? 2) The text keeps saying that Afr ican populations are in a state of high linkage disequilibrium, and Im assuming it is because they are in reproductive isolation. If mice are commensal with Africans as they are with separate human populations, do they exhibit the same LD? Can we then use them as a model to look at disease states and disease traits in Africans?