There are many reasons why you might want to take a DNA sample from you or your loved one. Various companies offer user-friendly DNA kits for home use for the purpose of paternity testing, genealogical testing, or genetic testing of disease. Many law enforcement agencies also encourage parents to take DNA samples from their children for identification purposes. There are various ways to take a DNA sample, and many of them are quite painless or intrusive. Depending on the sample, DNA can be stored for years if properly cared for.
Step
Part 1 of 3: Finding Out Your Needs
Step 1. Decide if you need a DNA device
This will depend on the purpose of the sample. If you want lab results for your sample, you may need to purchase a DNA kit. If you want to keep a sample in case you need it later, you may not need the device, although you can still decide to buy one, if you prefer.
The DNA testing kit has all the necessary equipment, comes with complete instructions and consent forms, which will be required if the sample is to be tested or kept on file by the authorities
Step 2. Find out the legal requirements
In most cases, DNA samples cannot be taken at home if they are to be used in court. While home paternity testing is useful for you to know for yourself, you may need to visit a lab and have your DNA taken by a specialist if the results need to be used in matters involving custody or child support.
Step 3. Choose the right type of sample
If you are using the device, there will be very specific instructions on the type of sample to be taken. If you're sending the sample to a lab without equipment, check with them so you know what type of sample you prefer.
- Most DNA kits require samples from swabs in the oral cavity (cheeks) or saliva. Hair samples are also a popular choice.
- It is possible to decipher DNA from almost all human body samples including nails, blood, sperm, and objects containing saliva, such as chewing gum. However, some samples are easier to parse than others. If you choose a sample type that is not a laboratory choice, they may not be able to parse the DNA, or they may cost more.
Part 2 of 3: Maintaining Specimen Quality
Step 1. Do not touch the sample
No matter what type of sample you take, do not touch it with your hands or place it on a contaminated surface. This is especially important if you are sampling someone else's DNA because you could potentially contaminate the sample with your own DNA.
Wash your hands before starting and always wear gloves
Step 2. Use sterile equipment
If the collection involves cotton swabs, tweezers, or tongs, these equipment must be sterile, and avoid touching the parts of the instrument that will come into contact with the specimen.
Metal utensils can be sterilized using alcohol or boiling water
Step 3. Store the specimen in a clean and dry container
The device will provide a series of containers as well as instructions for storing them properly.
- Paper envelopes are the best storage container for most non-liquid samples. Do not store hair specimens or damp oral swabs in plastic, as these will retain moisture and potentially damage DNA.
- If you store the specimen in an envelope, do not lick the seal, as this could contaminate the sample.
- If you wish to save the specimen for possible future use, label the name of the person from whom the specimen was collected, the date the sample was taken, and the name of the person who collected it.
- Store your sample away from moisture, temperature extremes, and chemicals.
Step 4. Follow the package packaging and shipping instructions
If you are using a DNA kit, the instructions will be very clear, so follow them carefully. If you are sending samples to the lab without using a device, make sure the shipping instructions are clear.
Part 3 of 3: Sampling
Step 1. Wipe the inside of your cheek
For oral swabs, scrape the inside of the cheek with a sterile cotton swab for up to one minute. Scrape hard, but don't hurt. Continue rubbing for at least 30-60 seconds. When you're done, make sure not to touch the tip of the cotton swab on any surface other than the inside of the mouth and the inside of the container.
- Devices often require more than one swab, just in case one doesn't contain DNA. If you're not using your device, you may still need to use a few swipes. To increase the amount of DNA collected, take two (or more) samples from different sides of the mouth, or take them several hours apart.
- Avoid eating and drinking anything other than water, smoking, chewing gum, brushing your teeth, or using mouthwash for at least an hour before taking the sample.
- Rinse your mouth with warm water before wiping it. If you are testing on a baby, let him drink water from the bottle before testing.
- Let the cotton dry before storing.
Step 2. Pull 10 to 20 strands of hair from the head
When taking a hair sample, pay attention to make sure the hair follicles, which look like little white balls, are still attached.
- Avoid wearing hair from combs or clothes. You also can not use a haircut.
- Do not touch the ends of the hair follicles.
- Taking a hair sample can be painful, especially if your hair is shiny and strong.
Step 3. Take a saliva sample
The easiest way to do this is to spit on your storage container. If you use a device, a sponge may be provided to facilitate the removal of spit from small children.
- Avoid eating and drinking anything other than water, smoking, chewing gum, brushing your teeth, or using mouthwash for at least an hour before taking the sample.
- Rinse your mouth with warm water ten minutes before taking the sample, to remove any food particles. If you are testing on a baby, let him drink water from the bottle before testing.
Step 4. Take another sample with the same care
If you want to take less common samples, such as fingernails, blood, or semen, be careful about everything to avoid touching them, otherwise it will contaminate them. Check with the laboratory you are sending the specimen to to make sure they can decipher the DNA from the sample you are taking.
