A DNA profile is a specific pattern of codons unique to each person, they are found in regions known as polymorphisms. Within polymorphisms, genetic regions vary among individuals. By identifying the DNA profile of a person investigators can compare this information with other DNA to see if it matches. This may be used to prove a genetic relationship between two people (such in a paternal case, where the mother is arguing that her child belongs to a certain man so that it is not just her responsibility. THis information can also prove that a suspect in a criminal case was indeed at the crime scene. Investigator may find urine, hair, skin, or blood on the scene that contains genetic information that investigators can use.
DNA Profiles can be split into two catergories: Variable Number of Tandem Repeats (VNTR) and Short Tandem Repeats (STR). STR Profiles are usually 2-5 bases in length and are much easier and faster to analyze, whereas VTNR Profiles are anywhere from 9 to 80 bases in length and take a long time to analyze. Both types of profiles can be used to match tissues (such as blood or urine) and reveal genetic relationships.
When matching tissue, a sample can be traced back to a suspect if a band pattern present in the DNA is identical to a band pattern taken directly off of the suspect. When performing inheritance tests, each band in the child's DNA must be present in at least one parent.
For example, in the photo below, it can be concluded that Suspect 2 was at the crime scene because the DNA evidence found at the crime scene matches his/her own DNA.
DNA Profiles can be split into two catergories: Variable Number of Tandem Repeats (VNTR) and Short Tandem Repeats (STR). STR Profiles are usually 2-5 bases in length and are much easier and faster to analyze, whereas VTNR Profiles are anywhere from 9 to 80 bases in length and take a long time to analyze. Both types of profiles can be used to match tissues (such as blood or urine) and reveal genetic relationships.
When matching tissue, a sample can be traced back to a suspect if a band pattern present in the DNA is identical to a band pattern taken directly off of the suspect. When performing inheritance tests, each band in the child's DNA must be present in at least one parent.
For example, in the photo below, it can be concluded that Suspect 2 was at the crime scene because the DNA evidence found at the crime scene matches his/her own DNA.