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. used for criminal Investigations / example of use in criminal investigation used to check paternity / who is the father / mother / parent used to check whether two organisms are clones 4. Outline DNA profiling (genetic fingerprinting), including one way in which it has been used. 5 marks SL and HL DNA profiling: 4 max sample of DNA / blood / saliva / semen is obtained reference samples of DNA are obtained PCR used to amplify / produce more copies of the DNA DNA broken into fragments by restriction enzymes DNA fragments are separated by gel electrophoresis DNA separated into a series of bands bands compared between different samples if pattern of bands is the same then DNA s (almost certainly) from same source if some bands are similar then individuals are (almost certainly) related specific example: 1 max testing of paternity / forensics / classification / archeology / another specific example 5. Outline a technique for transferring genes between species. 5 marks SL and HL gene of Interest is cut out with restriction enzyme RNA used to produce DNA using reverse transcriptase plasmid cut open with same restriction enzyme gene inserted into plasmid blunt ends / sticky ends spliced together by DNA ligase . recombinant plasmids are cloned / many coples produced . recombinant plasmids are Inserted into new host cells / virus / bacteriophage / yeast « inserted by shooting / spraying / microencapsulation / by heat treatment 6. Describe the technique for the transfer of the insulin gene using E. coll. 6 marks SL and HL « mRNA is extracted « DNA copy of RNA is made using reverse transcriptase . plasmids are cut open with endonucleases (at specific sequences) « Insulin gene and plasmid are mixed together . addition of 'sticky ends’ to the DNA copy (so that it will combine with the cut plasmid) . DNA ligase will seal the plasmid . recombinant plasmid is inserted into E. coll « E. coliis cultured . E. coll begins to make insulin 7. Discuss the potential benefits and possible harmful effects of genetic modification. 7 marks SL and HL . named example of desired outcome e.g. herbicide resistance Award 6 max if no named example given. Award 5 max if both possible benefits and possible harmful effects are not addressed. Possible benefits: 4 max . benefits include more specific (less random) breeding than with traditional methods . faster than traditional methods . some characteristics from other species are unlikely in the gene pool / selective breeding cannot produce desired phenotype