dna profiling

forensic dna analysis

It has the potential to individually identify a particular suspect

Forensic DNA analysis identifies individuals, closely related relatives, remains of mass disaster war victims, and missing persons.

dna profiling

Techniques that identifies a person based on their genetic code; No two people share the same DNA, Exception is identical twins, DNA is inherited from the mother and father, Can be used to determine kinship (closely related individuals)

CODIS

a database of arrestee’s DNA, collects, analyzes, and communicated criminal DNA information among law enforcement agencies, maintains DNA profiles of missing persons and unidentified human remains period

limiting factors

cost, time log, backlogs, instrumentation

DNA identification act

provides funds to improve labs and communication between law enforcement organizations period; new rapid dna testing kits (90 min)

science of dna

all human cells contain dna (except red blood cells), contains dna in cells nucleus (nuclear dna), structure of dna is a double helix which resembles a twisted ladder

chromosomes

Structure where nuclear DNA is stored.

46 chromosomes are found in the human body. They are composed of tightly coiled DNA molecules wrapped around proteins.

Each parent contributes 1 member of each pair of the 22 chromosomes plus one sex chromosome (male XX, female XY)

Your genetic code is composed of half of your mother's chromosomes and half of your father's chromosomes.

genes

basic units of heredity; human gene DNA sequences are 99.% the same, the 0.1% is what makes us different; alternative forms of a gene are alleles

precautions to avoid contamination

Use disposable instruments

Wear disposable gloves and change them often

Avoid touching areas where DNA may exist

Avoid touching your face

Never put two sources of DNA in the same bag

preservation of dna evidence

Keep DNA evidence dry, cool, and out of direct sunlight during transportation and storage

Moisture

Humidity

serologist

One who specializes in the analysis of blood serum, saliva, semen, and other bodily fluids; determine if source is human

mtDNA

is responsible for cellular respiration and energy.

Only the mother can pass mtDNA to her offspring and thus maternal ancestry can be traced using this type of DNA.

Unlike the limited amount of DNA found in nuclear DNA, the mitochondria can supply thousands of copies.

genetic genealogy

ancestry kits; mouth swab; family tree; public genealogy databases; relatives with partial matches; some consider violation of 4th amendment right to privacy

dna phenotyping

Through computer analysis a composite sketch of a person, including sex, eye color, skin tone, hair color, freckling, and facial structure is produced based on their genetic profiles.

Forensic artwork using age progression programs shows changes to the person over time including facial hair, loss of hair, glasses, wrinkles, and body weight.