DNA profiling

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Created by
jiachee

Cards (10)

  • DNA profiling protocol
    • DNA extraction from cells obtained from tissues such as skin, saliva, vaginal fluids, and blood
    • Cutting the DNA molecule using restriction enzymes into shorter fragments of different lengths
    • Separating DNA fragments of different sizes by gel electrophoresis
    • Measuring the length of fragments in kilobases
    • Showing the pattern of bands of fragments using fluorescent probes as markers
  • Variable Number Tandem Repeats (VNTR)
    The base sequence or the variable length of a hypervariable sequence of bases in the non-coding regions of the DNA molecule, unique to an individual
  • The base sequences or length of the hypervariable segment is similar in identical twins and chances in similarities in DNA profile of two non-related individuals is one in a million
  • Tandem repeats
    Short sequences of DNA that are repeated at a specific chromosomal locus, interspersed throughout the human genome
  • Short Tandem Repeats (STRs)
    Tandem repeats where the number of repeated units vary between individuals, termed STRs
  • Successful incorporation into modified rice genome
    Extract DNA, cut introns with one restriction enzyme, separate the DNA profile using electrophoresis to obtain a pattern of bands or DNA profile
  • Techniques for DNA analysis
    • RFLP
    • VNTR
    • STR
  • Techniques for DNA analysis - RFLP
    Extract DNA, cut using a restriction enzyme, then the sequence of the DNA fragment is determined (Electrophoresis and DNA sequencing)
  • Techniques for DNA analysis - VNTR
    Extract DNA, cut using a restriction enzyme, then the sequence of the DNA fragment is determined (Electrophoresis and DNA sequencing), Sequence fragment at the same loci or different loci to identify differences in the sequence (ATC or ATG) or the number of repeats (ATC x20; ATC x25)
  • Techniques for DNA analysis - STR
    Extract DNA, cut using a restriction enzyme, then the sequence of the DNA fragment is determined (Electrophoresis and DNA sequencing), Sequence fragment at the same loci e.g. 501, chromosome 8, an STR and DNA sequence is between 8-10 which is shorter and more specific compared to VNTR (ATC x3; ATC x 5)