Biology 2581B Lecture Notes - Lecture 13: Polytene Chromosome, Chromosomal Rearrangement, Cri Du Chat
28 Apr 2016
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Document Summary
Mouse versus human genome: at the sequence level, there are many similarities as well as same types of genes with similar sequences, however, when comparing chromosomes, the staining pattern of chromosomes suggests there is no conservation. For starters, 20 mouse vs 23 human chromosomes are present. After both genomes were sequenced, each mouse chromosome could be pieced together from different human chromosomes. This means that all the pieces of genomes containing similar sequences were present, but they were all on different chromosomes: the mouse genome could be aligned with the human genome once it was broken into 100s of fragments. This shows that chromosomes come in different sizes and content, and that there was lots of chromosomal rearrangements between humans and mice, over time. Syntenic segments: these are when genes are lined up in the same order along various chromosomes of different organisms. These segments allow identification of genes, and ordering of genes.
