The majority of transposable elements in human genome are dormant representing

The majority of transposable elements in human genome

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The majority of transposable elements in human genome are dormant, representing fossils of transposition events that took place in ancient times Activation results in genetic disease (hemophilia, muscular dystrophy, etc.) The L1 element:
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Retroposon belonging to a class of sequences known as LINEs Genome contains 3000-5000 complete L1 elements and +500000 shortened L1 elements Complete are about 6kbp long, have an internal promoter, 2 open reading frames encoding a nucleic-acid binding protein and a protein with endonuclease and reverse transcriptase activities SINEs (short interspersed nuclear elements): Second most abundant class of transposable elements in human genome SINE families are Alu, MIR, Ther2/MIR3 SINEs are usually less than 400bp long and do not have encode proteins Reverse transcript required for the SINE transposition is provided by a LINE-type element Transposable elements: evolutionary implications and applications in genetics, biotechnology and potential gene therapy They are used by researchers as tools to create mutant lines for genetic analysis and for genetic engineering A Transposable element as vectors for transformations Mutagenesis (1970s and 1980s), Rubin and Spradling caused the transformation of Dresophilia using the P element derived double vector Transposon tagging has been use as a standard technique to induce mutation in many organisms Mutated genes contain a tag for easy identification Foreign DNA is inserted into an incomplete P element and mixed with complete P element in solution, this is inserted into a mutant embryo, the embryos complete germ line transposase from the complete P element catalyzes the excision of the incomplete P element from its plasmid and it is inserted into chromosome of the embryos germ line
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Resurrection of the dormant marinertransposase gene via genetic engineering ‘sleeping beauty’Most of the transposable elements are disabled through mutation in that transpose geneAssembly of mariner genes from various fish and mapping of the consensus sequence based on the majority rule Reconstruction of the mariner gene based on mutagenesis and the dormant mariner gene is resurrected Transposon (T-DNA) insertional mutagenesis: Arabidopsis thaliana has been a very important model organism for plant research Insertional mutagenesis using transposon tagging and T-DNA all of the 26000 genes could be tagged to produce large numbers of mutant lines There have been many international forces to tackle this problem (Ohio State University, France, Germany, Japan etc.) Transposon and chromosome structure: Transposable genetic elements are powerful mutagens and play an important role in evolution, they have also been implicated in the formation of chromosome rearrangements Crossing over may occur between homologous transposons located at different positions on the same of different chromosome. These events are referred to as ectopic intra-
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