Role of DNA in Forensic Science

To amplify DNA

To label DNA fragments

To visualize DNA

To extract DNA

VNTR sequences are longer than STR sequences

STR sequences are more variable than VNTR sequences

VNTR is used for DNA analysis more than STR

STR sequences are usually 9-80 bases in length

VNTR and STR

DNA and RNA

Protein and Lipid

Chromosome and Gene

Male 1

Male 2

Neither could be the father.

Bob

Sue

John

Lisa

Suspect #1

Suspect #2

Suspect #3

They have the correct child, because her genetic information is identical to that of the father.

They have the wrong child, because her genetic information does not match that of either parent.

They have the correct child, because her genetic information matches the genetic information from both parents.

They have the wrong child, because her genetic information matches only that of the mother.

They have the correct child, because her genetic information is identical to that of the father.

They have the wrong child, because her genetic information does not match that of either parent.

They have the correct child, because her genetic information matches the genetic information from both parents.

They have the wrong child, because her genetic information matches only that of the mother.

Couple W

Couple X

Couple Y

Couple Z

DNA Fingerprint

Allele

Chromosome

Allele

Restriction Enzyme

DNA Probe

STR (Short Tandem Repeat)

PCR (Polymerase Chain Reaction)

VNTR (Variable number of Tandem Repeats)

Most genes are dominant

All organisms contain RNA

The most important genes are different among most people

No two people, except identical twins, have exactly the same DNA 

Electrophoresis

DNA Fingerprint

DNA Probe

DNA is negatively charged so attracted to the positive end of the unit

DNA is positively charged to attracted to the negative end of the unit

the agarose gel in negatively charged

the agarose gel is positively charged

Allele

Chromosome

DNA

PCR (Polymerse Chain Reaction)

Electrophoresis

DNA Probe

Use disposable gloves and collection instruments

Avoid physical contact, talking, sneezing, and coughing

Air-dry evidence and put it into new paper bags

Keep evidence cool and dry during transportation

To cut the DNA into fragments

To amplify the DNA

To stain the DNA

To preserve the DNA

Isolating cells from biological evidence

Disrupting cells to release DNA

Extracting DNA from the cell nucleus

All of the above

To identify unique sequences in a person's DNA

To create synthetic DNA bases

To bind to non-complementary bases

To analyze RNA sequences

Match crime scene DNA with a suspect

Determine paternity

Eliminate a suspect

Identify human remains

It contains coding sequences

It is used for energy production

It contains unique patterns for identification

It is irrelevant to DNA analysis