DNA Phenotyping

What is DNA Phenotyping?

• DNA Phenotyping is the prediction of physical appearance from DNA,utilize a strand of DNA to recognize an individual's conceivable hair and eye shading, and additionally skin pigmentation and family. With this information, law enforcement can then produce a computer produced picture of the suspect.

• FDP is a relatively new practice in the field of forensic science and relies on genotypic mapping and already obtained information on the genome in order to make its phenotypic predictions.

• DNA phenotyping is a technique that is typically used within the context of an unsolved crime when there are no potential perpetrators identified and no other evidence or eyewitnesses that can yield any reliable details about their identity

Cocerns about DNA Phenotyping

• Since race is not a valid or coherent construct in much of the scientific community, the identification of perpetrators based on the ‘racial’ group that they belong to may obscure the ability of law enforcement to objectively identify the perpetrator (mixed individuals)

• There are many arguments about DNA phenotyping because it violates many induvial rights which include: privacy, racial discrimination, equality, and civil liberty

• The current FDP technology only allows for the identification of individuals by ‘race’ alone, rather than including additional details such as the height, weight, gait, or other characteristics that would help significantly to narrow down the unknown perpetrator

• Another ethical issue is disease linked appearance. “The use of disease information obtained from DNA can be viewed not appropriate for forensic purposes with the ethical argument that patient discrimination is to be avoided” (Kayser 45). Some disease phenotypes reflects normal phenotype so you would not be able to tell the difference.

Pros/Cons

DNA Phenotyping

In catastrophic events, DNA phenotyping is a good method. “Forensic DNA phenotyping is also expected to be useful for missing persons identification, i.e., in cases where reference DNA profile from putative ante-mortem samples, or from putative

relatives are unavailable

You can alter your appearance in many ways that can affect DNA phenotyping and making it inaccurate. You can color your hair or shave it off,

grow a mustache, eat well or inadequately, lose or put on weight, turn into an addict, get distorted in a mischance, glasses, get an excess of sun, smoke, help or obscure your skin, have

plastic surgery, change sex, and do numerous different things that can influence your appearance

yet which have zero attach to your facial DNA

(False conviction and unsolved case)

When the physical appearance of an individual is unclear, DNA phenotyping helps create a picture of unidentifiable bodies and make them recognizable to family members. DNA phenotyping help bring closure to many families from tragic events.

Snapshot costs $3,600 per phenotype analysis

Another issue is that many families tend to look alike. If DNA phenotyping comes up with an actual image, it may look like many people. This method is inaccurate and may cause many problems in the Forensic field.

What type of DNA Phenotping?

• There are two types of DNA phenotyping: Indirect and Direct

• Indirect phenotyping allows the tester to obtain information about the visible characteristics of the organism to which the DNA belongs to. This may refer to, “…skin color, hair shape, and shape of the eyes and face” In addition, the organism’s geographical origin may be determined through this method of DNA phenotyping as well

• Direct DNA phenotyping may yield information about the organism’s body features or behavioral characteristics

• Currently, in forensic science, DNA phenotyping is able to predict one’s skin pigmentation and other very common ‘group-specific’ features with extraordinary precision. However, this is not the case with many other individual, group-specific features

History

• The first known company to publicize its use of DNA phenotyping as a methodology was ‘DNAPrint Genomics’. However, the company ceased to function after a very short amount of time due to its controversial practices (Johnston, 2002). The company initially marketed its services as a way for individuals to verify their ancestry or confirm their racial composition to see if they identify for various scholarships.

Snapshot DNA Phenotyping became available for law-enforcement agencies in late 2014, Parabon NanoLabs.

NanoLabs provided a phenotype DNA analysis to more than 100 law-enforcement agencies in the United States and Canada, and 13 of them led to an arrest of a suspect.

Snapshot makes it possible to predict a person's face with at least 1 nano gram of DNA, which can easily be acquired in most crime scenes.

Nanolabs conducted many blind tests to see how closely Snapshot generated an image of an unknown person. The results were similar to the person's appearance.

The current version of Snapshot doesn't predict age, height or weight

Major Cases that have been affected by DNA Phenotyping

In 2012, during a visit home from college, 19-year-old Whitley French woke up early in the morning to find herself facing a masked intruder in her Reidsville, North Carolina bedroom. When she screamed, Whitley’s mother and father came running. The intruder shot and killed them and then fled. Whitley survived.

The killer left five drops of blood on the staircase, but an analysis of the DNA it contained failed to produce a match with any suspects or anyone in public databases. For three years, the double-murder remained unsolved.

In early 2015, law enforcement authorities contacted Parabon NanoLabs, a Reston, Virginia-based company that had just started offering a DNA phenotyping tool called Snapshot. From the DNA in those old drops of blood, the company predicted that the killer had fair skin, dark hair, and was of European and Latino ancestry.

Armed with those clues, detectives took a closer look at the family of Whitley’s fiancé and found that the blood at the crime scene matched that of Whitley’s soon-to-be brother-in-law. He was arrested in June 2015, less than a month after serving as a groomsman in Whitley’s wedding. He pled guilty and is now serving two life sentences.

A couple were gunned down by an intruder in their North Carolina home in the early hours of Feb. 4, 2012. The teenaged daughter had seen the hooded gunman, when he had briefly held a knife to her throat, but she could apparently not describe him to cops.

The attacker left several drops of blood on a handrail as he fled, apparently self-inflicted from his blade. In this case, the blood showed the killer to be someone with mixed ancestry – apparently someone with one European and one Latino parent.

During the first year of the investigation into the murders of Troy and LaDonna French, detectives swabbed more than 50 people for DNA, including the daughter’s boyfriend. The trail of evidence went cold for months, and then years.

DNA told investigators there were no matches with known friends or family of the Frenches – and the killer was not in any of the public databases. Further analysis then indicated that the daughter’s boyfriend, John Alvarez (who had given a swab), could be related to the killer.

Y-STR analysis appeared to eliminate two close relatives of John Alvarez, both Jose Alvarez Sr., and Jose Alvarez Jr.

DNA phenotyping revealed Jose Alvarez, Jr., was the killer (was not biologically related)

He was arrested in August 2015 and charged with two counts of capital murder. He later pleaded guilty to killing the Frenches, and was sentenced to two consecutive life sentences without the possibility of parole in July 2016.

Unfortunately, phenotyping is still a developing science; there is a long way to go before it is commonly used.