Introduction
You have asked me to research DNA test kits, which are tests that analyze a sample of an individual’s DNA and look for specific characteristics associated with different conditions. These tests can reveal genealogical information, health information, and also establish legal paternity. DNA tests can also be used in forensic science to help solve active cases.
Background
DNA, which is short for deoxyribonucleic acid, holds the entire story of a person’s past, present, and future. It makes an individual who they are because it can determine multiple characteristics or traits. Some of these traits include hair and eye color, height, and even diseases that a person may or may not be at risk for. The study of DNA can also help fill in the blanks on a family tree. Many questions can be answered through the use of a simple DNA test. But how is this test performed? How does the DNA test actually work?
During DNA testing many people may be curious about the actual process that goes on. This type of testing involves an enormous amount of scientific knowledge. This testing procedure is performed in doctors’ offices and several laboratories. There are many steps to administering the test and testing the DNA.
The first step of the testing process is collecting a sample. These samples can be hair or bodily fluids from the individual. The most common and easiest samples to collect are saliva and buccal (cheek) cells. Buccal cell swabs are a non-invasive way to collect a person’s DNA.
To collect the buccal cells, the patient must first rinse their mouth with mouthwash. This will remove leftover food or drink that may affect the sample quality. Next the patient will swab the inside of the cheek for a couple of seconds. This is removing a layer of cheek cells to be tested. Then the patient will gently remove the swab from their mouth. Lastly, the sample will be given to the medical examiner so it can be packaged and sent to the laboratory for testing.
After the DNA sample arrives at the lab, it must go through lysis. Lysis is the process of breaking down the cells by a viral, osmotic, or enzymatic mechanism. Cell lysis is performed to open up cells to avoid forces that would destroy sensitive proteins and DNA. Next, the separation process must be done. There are numerous ways to separate DNA. The most common process to separate DNA is called gel electrophoresis. This technique separates DNA fragments based on their size and charge. DNA samples are put into wells at one end of a gel, and an electric current is used to pull them through the gel.
The next step in the DNA testing process is copying DNA. This process is known as the polymerase chain reaction (“PCR”). Copies made from the PCR can be used in many laboratory procedures. After the copies are made, they can be sent to be tested for genetic markers.
When administering a DNA test, there are many types of tests to choose from. The three most common tests are autosomal DNA testing, Y-DNA testing, and mitochondrial DNA testing (mtDNA testing). These tests are different from each other in several ways. To get a full understanding of the differences between these tests, it is best to know how DNA is arranged. DNA is the code in all of your cells. It comes in long stretches known as chromosomes. Every human usually has 23 pairs, which equals 46 chromosomes.
The first test type is autosomal DNA testing. Autosomal DNA testing evaluates you DNA that comes from your parents—the 22 pairs of chromosomes called autosomes. According to an article from AncestryDNA, these tests analyzes your genetic code at about 700,000 different locations, or markers, across your autosomes. These chromosomes hold information that can help you determine several facts about an individual and their family members.
The second test type is Y-DNA testing. The test analyzes one chromosome in the 23rd pair, the Y-chromosome. This chromosome can be used to test the male line or patrilineal history. Y-chromosomes are passed down from a person’s biological father, who inherited it from their father, and so on. Women don’t have the Y-chromosomes, so they aren’t able to take Y-DNA tests. The last type of DNA test is mitochondrial DNA testing. This test analyzes a part of DNA that is found in the mitochondria of cells. Mitochondrial DNA testing examines the female line or matrilineal history of a person. The mitochondria of an individual are passed down from the biological mother’s egg. These three tests all evaluate different sections of DNA and they all help reveal different aspects of individuals.
What do DNA Test Kits Reveal?
Genealogy
When scheduling or purchasing a DNA test, individuals may be looking forward to finding numerous amounts of information. As stated before, DNA is the code in all your cells. It makes every individual who they are and who they will be. It can determine multiple characteristics or traits. Some of these characteristics that DNA test may reveal include where certain physical features come from, health and medical information, and genealogy. Some DNA tests can also be used to establish legal paternity.
One of the most common reasons that DNA tests are given is to reveal genealogy, which is a record of the ancestry and descent of an individual and that individual’s family. Brands including AncestryDNA examine people’s genetic code and science to to gain clues about their family history, relationships, and ethnic origins.
The most relevant reason for taking a DNA test is to reveal who you may or may not be related to. Most DNA test companies use customer information to compare profiles. When comparing these profiles, the company looks for segments of DNA that suggest that some individuals might be related and a shared ancestor. According to an article published by AncestryDNA, companies can also predict the type of relationship between individuals based on the amount of DNA they share. For instance, a grandparent and grandchild will have the relationship status of immediate family because they share about 25% of DNA.
These companies also allow their customers to see whether other users of the service can be related to them. This can be beneficial when an individual is trying to create a family tree. By giving customers this option, they are able to fill in blanks on a family tree and also learn about their biological family. In an article written by Nicole Haloupek, she expresses that “ Several people have discovered siblings they never knew they had through these services. In one case, two women—one adopted through an agency and another adopted by a family who found her in the woods as a baby—realized they were long-lost sisters.”
While some people take these tests to reveal familial relationships, others use these tests to reveal their ethnic origins.
Establishment of Legal Maternity or Paternity
Another big reason individuals get DNA tests performed is to establish legal maternity or paternity. Maternity DNA tests determine whether a female is the biological mother of an individual. on the other hand, paternity DNA tests determine whether a male is the biological father of an individual. These two tests are very similar to each other. DNA paternity test compares an individual’s DNA pattern with the DNA pattern of the assumed father to determine if there is a match. The DNA maternity test works just like a paternity test, but instead it compares the child’s DNA to the mother’s.
Maternity and paternity DNA tests are often requested to solve numerous legal cases. When the DNA tests are completed, the results can determine whether a person has any responsibilities they need to fulfill for their child. This may include paying child support. These tests also determine if an individual is qualified to take custody of the child.
Health & Medical Information
DNA tests are a very useful tool in the healthcare field because it reveals tremendous amounts of information about a patient's body. These tests analyze an individual's DNA sample and look for variations that are associated with different conditions. Some DNA tests are also used to diagnose and predict an individual's chance of developing a specific illness.
As stated previously, DNA tests can confirm whether an individual has a certain hereditary disease. Doctors will use these tests to help determine a genetic disease diagnosis in someone who is experiencing certain symptoms.
DNA tests can also determine whether or not an individual's DNA contains a mutation for a genetic disorder that may affect their future children. According to an article by Insider people who are fully healthy might have mutations in their DNA that are linked to some genetic disorders. This is known as being a carrier, which means their DNA obtained one copy of a gene mutation for a specific hereditary disease or condition. The disease doesn’t usually affect the carrier or their health. This is because the carrier’s DNA still had another copy of that specific gene that doesn’t have the mutation. (Swain-Wilson, 2019)
For instance, if someone is a carrier for the disease mutation associated with cystic fibrosis, it doesn’t mean they have cystic fibrosis. But there is a 50% chance that the individual will pass down a copy of that mutation to their children or future children. Insider also spoke with Dr. William G. Feero, who explained that when two future parents are carriers of the same genetic disorder, their child may develop the disease.
He also told Insider 'If a woman is a carrier of a mutation for cystic fibrosis, and her partner is also a carrier of a mutation in one of his cystic fibrosis genes, their baby has a one in four chance of inheriting two bad copies of those genes. [As a result,] there's an increased chance that the baby will be born with cystic fibrosis.'
DNA Testing in Forensic Science
Although DNA tests are commonly used by consumers who want to reveal genealogy, health and medical information, and determine legal paternity, they can also be used by the authorities and forensic scientists. The law enforcement and forensic scientists will use the DNA to catch criminals, close cases, and exonerated individuals that have been wrongfully convicted. The use of DNA testing in a forensic setting is know as forensic DNA testing. The use of forensic DNA testing is used all over the world and is portrayed in many television shows. Many television shows including Forensic Files, Cold Case, and Law and Order: SVU have all helped enhance the knowledge of others about the need of forensic DNA in solving crimes.
DNA evidence has become very useful and reliable over time. This is because it can be found all over the human body. DNA can be obtained from hair follicles, blood and bodily fluids, and under fingernails. Samples can be found from head to toe. DNA samples can also be found on clothing, bed sheets, weapons, and discarded items including tissues and condoms. Similar to the other DNA tests, DNA samples used in forensic testing should be swabbed and preserved so no damage is done.
After the DNA evidence is collected, it will be analyzed and compared to another sample to determine if there is a match. There are four possible results that can occur after a forensic DNA test is administered. These potential results include: inclusion, exclusions, inconclusive result, and no DNA obtained. Forensic tests with inclusions will happen when a sample is consistent with the unknown sample from the crime scene. Exclusions occur when the sample provided doesn’t match the DNA sample from the crime scene. The third type of results are inconclusive results. These type of results occur when the unknown results yield partial or no results. This will also occur if no suspects are available to compare to the DNA retrieved from the crime scene. The last type of results is no DNA being obtained, which means that no DNA was able to be extracted from the sample that was provided. (DNA Diagnostics Center, 2014)
When conclusive DNA test results have been obtained, they have many abilities in the legal system. As mentioned before, DNA is useful in court convictions, cold cases, and exonerations. Many cold cases have been solved due to the use of DNA evidence and DNA national databases such as CODIS. One known case that involved the use of DNA to catch the criminal was the case with the Golden State Killer.
Crimes Committed
The Golden State Killer is believed to be associated with more than a dozen homicides and about 50 tapes across California. The case is believed to have begun in June 1976, when a women from Citrus Heights, a city in Sacramento County, reported that she was raped by a masked intruder. Following this attack, there were a number of attacks that occurred in and around Sacramento. After these attacks occurred, the police gave the suspect the name “East Area Rapist.”
When the attacks first begun, the reports usually involved women that were alone. But, the list of attacks progressed to couples who were in their homes. By 1978, the killer’s first known homicide was committed in Rancho Cordova, which is city located in Northern California. The Golden State Killer murdered Brian and Katie Maggiore. After the two victims were murdered in a Rancho Cordova, the killer committed a series of murders in the Santa Barbara area. For almost 10 years, this killed traumatized Southern California and he was given the name “Original Night Stalker.” (Hare & Taoushiani, 2019)
While the attacks were going on, law enforcement did not see a connection between the attacks in the two areas of California. But, then they noticed a pattern. When the serial killer committed theses crimes, he would break into homes at night. If there was a couple home, he would tie up the male and place plates on his back. If the killer heard any played fall while he was raping the women, he would kill both victims. Retired detective for Contra Costa County Sheriff’s Department stated:
'Over the years, we heard of homicides down in Southern California, and we thought it was the East Area Rapist. But he would not leave fingerprints, so we could not prove, other than his M.O., that he was the same person. We did not know anything about DNA.'
The Arrest
In 2001, DNA tests confirmed that the East Area Rapist and the Original Night Stalker were the same suspect. Then in 2018, which was 42 years later, DNA led to the arrest of Joseph James DeAngelo Jr., who was a cop during the years of the first crime spree. Investigators use a genealogy and DNA database known as GEDMatch to track down the killer. The suspect left behind DNA at the crimes scene of a 1980 murder. After having the DNA analyzed, the authorities created a fake profile in GEDMatch and uploaded the data hoping it would lead to some relatives of the killer. This DNA sample led the investigators to relatives of DeAngelo and genealogy experts created a genetic trials leading to DeAngelo himself. (Halouopek, 2018)
The Charges
According to an article by CNN, DeAngelo is facing 13 counts of murder with special circumstances, including murder committed during the course of a burglary and rape, as well as 13 counts of kidnapping for robbery. He has been in six counties which are Sacramento, Santa Barbara, Orange, Ventura, Tulare and Contra Costa. The Golden State Killer will be tried on the multiple murder counts in a single trial in Sacramento. Prosecutors are asking for the death penalty in every county except Tulare and Contra Costa, because they aren't eligible for that sentence.As of today, he is still in jail.