DNA Testing

DNA testing is a complex scientific process, which is the most accurate technology, to determine the relationship between individuals. Indeed, every human has DNA inherited from parents. It is different even if sibling of the same mother, except identical twins. Thereby, DNA testing that can summarize interpersonal consanguinity, is the most recognized method to prove interpersonal relationship in the family.

DNA testing services are as follows:

  1. DNA Paternity Testing

DNA paternity testing is to compare DNA profile of a child and a person accused as father. The child is inherited half DNA profile from the parents. Thus, by comparing DNA profile, it will reveal whether the child is inherited DNA profile from a person who is accused as father.

  1. DNA Maternity Testing

The sampling and testing process of DNA Maternity are similar to DNA paternity testing. DNA profile of a child and a person accused as mother will be compared. The test probably use a sample of father, but it is not necessary for the result.

  1. Sibling Testing

Sibling testing has 2 cases; siblings born from the same mother or father, and siblings born from the same mother and father.This type of testing can also be referred to paternity in case of no having a sample of the accused.

  1. Twin Zygosity Testing

Twin zygosity testing is to identify whether twins were born from the same ovum. Identical twins (born from the same ovum) have a similar DNA profile, so they can donate organs, tissues, blood to each other. If one of the identical twins has a genetic disorder, it is likely that another will have the disorder as well.

  1. Prenatal DNA Testing

Prenatal DNA testing can testify the paternity since the unborn child. The testing will compare DNA profiles of the fetus and the accused. It is necessary to collect a sample of mother for analysis, due to the sampling process of the fetus may be contaminated with the mother’s DNA.

  1. Grandparentage DNA Testing

Grandparentage DNA testing is to prove the consanguinity between grandparent and grandchild. The testing will demonstrate probability value of genetic relationship between grandparent and grandchild.

  1. Avuncular DNA Testing

Avuncular DNA testing is to prove the consanguinity between the avuncular and grandchild. Typically, genes of avuncular is only 25%similarity to the grandchild’s. Therefore, the result of testing will not be accurate, comparing with paternity DNA testing, because of gene’s dilutionby 2 times.  The testing will result probability value of the relationship.

*Note: Samples used in DNA testing such as cheek lining cells, hair follicles, toothbrushes, cigarette butts, bloodstain (or blood platelet), nails, gums, etc.

**Note: Duration of testing: within 3 days by specialists in laboratory accredited standard ISO / IEC. 17025: 2005, Department of Medical Science, Ministry of Public Health. For more information, contact detectives directly.

How to collect a buccal DNA sample by yourself

The process of sampling (the buccal DNA collection kit for 1 person contains 2 swabs)

  1. Take out the first swab (do not touch the cotton tip decisively) and use it to scratch and spin at left-side cheek bulge for 15 – 20 second (be careful not let cotton attached too much saliva). Then, turn its cotton up and leave it in a glass.
  2. Take out the second swab, and repeat the first step on right-side cheek.
  3. Place the swaps upright and leave it dry about an hour.
  4. Collect sample of another by following step 1 – 3
  5. When the swabs is completely dry, collect them in the envelopes provided(be careful not be alternate).
  6. Deliver the samples to detectives.

The process of collecting DNA sample from hair follicles

DNA testing will take a sample of hair roots only by following the procedures below;

  1. Wear gloves to prevent touching and contaminating hair roots.
  2. Collect 8 – 10 hair lines
  3. Store it in a plastic bag before delivering to detectives.

The process of collecting DNA sample from a toothbrush

A toothbrush, taken as a sample, should be used at least 2 months, and must not be shared with others. The amount of DNA depends on the duration of usage. The proper procedure of collecting the sample are as follows;

  1. Wear gloves to prevent the contamination. (do not touch a brush decisively)
  2. Leave it completely dry by placing its brush upright in a glass for an hour.
  3. Wear gloves and store the completely dry toothbrush in an envelope or a plastic bag before delivering to detectives.

The process of collecting DNA samples from cigarette butts

The amount of DNA depends on the quantity of cigarette butts, and collecting methods. Importantly, it should be contaminated. The proper collecting methods are listed below;

  1. Wear gloves to prevent the contamination.
  2. Collect 3 – 5 cigarette butts from an ashtray where the sample is more perfect than anywhere else.
  3. Store the cigarette butts in a plastic bag before delivering to detectives.

The process of collecting DNA samples from blood (blood or bloodstain)

Blood can be used as an example of DNA testing including blood directly drawn from the body, bloodstain on absorbed materials, dried blood stain, etc. Blood directly drawn from the body is highly effective and accurate as well as the testing of a buccal cell. Using bloodstain on absorbed materials or dried bloodstain may affect the accuracy of the test which its result can be unpredictable. However, it depends environment, degree of deterioration and contamination which are obstructions of DNA extraction. Blood should be drawn at the hospital, filled with EDTA to prevent blood clotting, and store at room temperature for 24 hours before delivering to detectives. To collect DNA from bloodstain or dried blood should be done as follows;

  • Wear gloves to prevent the contamination.
  • Store the sample in a clean plastic bag, close it tightly, and deliver to detectives.

By shipping samples to detectives, you must have name and address clearly. It will be used as a contact channel and to deliver the result.

The process of collecting DNA samples from fingernails

Fingernails can be used as samples of DNA testing. In the purpose of samples’ effectiveness, fingernail should be cut directly from hands or feet. Nail scraps should be avoided from direct contact to prevent the contamination. The methods of collecting are listed below;

  • Wear gloves to prevent the contamination.
  • Store the sample in a clean plastic bag, close it tightly, and deliver to detectives.

By shipping samples to the detectives, you must have name and address clearly because it will be used as a contact channel and to deliver the result.

The process of collecting DNA samples from amnioticfluid

Amniotic fluid can be used as a sample of DNA testing. You need to consult with an obstetrician to penetrate a sample of amniotic fluid. The testing will use approximately 1 ml. of amniotic fluid. It should be stored in a clean sterile tube, and shipped to the detective. During the shipment, the sample tube should be kept in a cold storage in temperature 4C ° – 8C °. You must have name and address clearly because it will be used as a contact channel and to deliver the result.

 

Question: Is mother required attending to the paternity test?

Answer: The paternity test is to demonstrate the relationship between father and a child.

Mother is not necessarily required to the test. However, if the mother’s sample is available, the result will be more accurate.

Question: How old is a child can get the DNA test?

Answer: A child can get the DNA test immediately since new born by collecting a sample of  buccal cells. This method is easiest, quick, and painless.

Question: How accurate is DNA testing?

Answer: DNA testing is to determine the interpersonal consanguinity. Thus, if a person, who has no consanguinity, gets the DNA test, the accuracy of the test result will be 100% confirmed that there is absolutely no relationship. In the contrary, the result will show value of reliability at 99.999%, if a person has consanguinity.