DNA fingerprinting genetic fingerprint Introduction and work instruction

DNA fingerprinting (genetic fingerprint) Introduction and work instruction about the procedure of the experiment DNA-Fingerprint 1

Content 1. 1. 1 1. 2 1. 3 1. 4 DNA fingerprinting introduction Areas of application Comparison classic and modern procedure DNA marker source Restriction enzymes DNA-Fingerprint 2

1. 1 Areas of Application ● ● Forensic identifying perpetrators e. g. with blood/ skin cells, hair, sperm Proof of foreign genes: - in Organisms (are they transgene? ) - in grocery (Are hamburgers made out of pure beef? Discovery of a biological father or mother Proof if twins are genetic identical DNA-Fingerprint 3

1. 2 Comparison Classic procedure • • Introns Minisatellites Modern procedure • • VNTRs 15 - 300 bp • • Restriction Gelelectrophoresis Blotting Hybridisation with VNTR-sond Introns Microsatellites STR 4 - 6 bp • • DNA-Fingerprint PCR Gelelectrophoresis 4

Advantages of a modern procedure • • DNA-areas are shorter with max. 5000 bp (vs. 20 000 bp) PCR is cheaper and faster (1 day) DNA-Fingerprint 5

Investigated DNA-Sections Intron 1 CCTATTA 5 times repeated • • Exon Intron 2 without CCTATTA Exon Intron 3 CCTATTA 10 times repeated Repititive sequences in the introns are individual different. Sequenz polymorphisms come up through differences at one single basepair one sequence of recognition gets lost different pattern of bands in the gel DNA-Fingerprint 6

1. 3 DNA Marker Source: Lambda. Phage • • hosted by E. coli Genom 48502 Bp head (1982 sequenced) • Genom is cuted by restriction enzyme Eco RI DNA-Fingerprint tale 8

1. 4 Restriction Enzymes – Eco. R 1 cuts sticky ends GAATTC CTTAAG (Providencia stuartii) CTGCAG GACGTC - Hae. III cuts blunt ends GGCC CCGG – Pst 1 DNA-Fingerprint 9