Understanding DNA testing
DNA tests are becoming popular for people curious about their heritage worldwide, and many donor-conceived people are using them if there are no clinical records about their donor.
DNA tests to establish a relationship or find relatives online are becoming more popular. In Australia, there are two types of DNA tests that donors and donor-conceived people can access:
- NATA (National Association of Testing authorities, Australia)-accredited DNA tests, which are often used to establish proof of a relationship between two people, such as paternity.
- Direct-to-consumer (DTC) DNA tests, which are also known as genealogical DNA tests or ancestry DNA tests. These tests involve a user providing a sample for analysis. Their profile can then be uploaded to a database to generate matches with other users.
Our DNA is made up of four tiny molecules called bases, which we can think of as the DNA alphabet: Adenine, Guanine, Cytosine, and Thymine (A, C, T, G).
These four letters make long chains of DNA called genes, which represent ‘words’ in our instruction book. These genes condense to form chromosomes, which can be thought of as chapters in the instruction book.
In each of our cells we have two copies of each gene – one from each parent. Our genes are condensed into 23 pairs of chromosomes. One pair of these chromosomes are the sex chromosomes (X and Y), which determine if we are biologically male (XY) or female (XX).
For DTC DNA testing, people can send a DNA sample (usually a cheek swab or saliva sample) to DTC companies without consulting a health professional such as a GP.
The company analyses your DNA sample and provides information about your ancestry based on information within your genome. The company may notify you if another individual in their database has a similar DNA profile to you. This may indicate a genetic relation and only occurs when a genetic relative has uploaded their results to the same DNA testing website as you.
How does it work?
All human genomes share 99.9 per cent of the same DNA. It is the 0.1 per cent that makes us unique.
DTC DNA tests investigate different sections in our genome called genetic markers which are highly variable within the human population. Through a process called DNA fingerprinting, scientists analyse these markers to create a unique DNA profile for an individual.
DNA ancestry testing examines your DNA profile and identifies certain markers in your genome that are more commonly found in one geographical group compared to another. This is how ethnic background is estimated.
Because we share some of our DNA with our genetic relatives (e.g. your parents, grandparents, cousins, etc.), your DNA fingerprint will partially overlap with those you are genetically related to. Ancestry DNA testing companies can determine the relatedness of individuals based on how many markers they have in common.
You share 50 per cent of your DNA with your mother and the other 50 per cent with your father. You will also share approximately 50 per cent of your DNA with siblings who have the same mother and father as you. The amount of DNA you share with other relatives decreases as the relationship becomes more distant.
|Type of genetic relationship*||Average % of DNA shared|
|Grandparent, aunt/uncle, niece/nephew, half-sibling||25|
|First cousin, half aunt/uncle/niece/nephew||12.5|
|First cousin once removed, half first cousin||6.25|
|Second cousin, first cousin twice removed, half first cousin once removed||3.125|
*The table above is a guide only. DNA testing companies may not be able to distinguish the exact relationship based on the result of one test alone and may only refer to genetic relatives as potential cousins.
To make test results more accurate, and/or to find more matches in an online database, it is recommended that blood-relatives also have a DNA test.
Types of DTC DNA tests
There are three types of DNA tests that can be analysed to determine your family origins. DNA testing companies may use a combination of the three.
- Y-chromosome testing (males only): Males always inherit their Y-chromosome from their father. Therefore, DNA testing companies are able to track your paternal lineage by specifically analysing your Y-chromosome.
- Mitochondrial DNA testing (mtDNA): Mitochondrial DNA (mtDNA) is DNA that is separate from your normal cells’ DNA sequence. As mtDNA from sperm is not transferred to the woman’s egg during fertilisation, all individuals inherit only their mother’s mitochondrial DNA. Therefore, this type of DNA testing can track your maternal lineage. There have been cases of inheriting mtDNA from fathers, but it is extremely rare.
- Autosomal DNA testing: This type of testing looks at all of an individual’s DNA, which can be used to track both maternal and paternal lineages. This type of testing provides information about your overall ethnic background.
As millions of people embrace ancestry DNA testing globally, more people are discovering they were donor-conceived. If this has happened to you, you are not alone. VARTA is here to support you.
How does genetic testing link relatives?
When people participate in DNA ancestry tests, companies often provide a choice to connect with genetic relatives around the world. As we all share some of our DNA with our relatives, including our parents, grandparents, siblings, and cousins, our DNA fingerprint partially overlaps with those we are genetically related to. As DNA companies receive more test results, they can increasingly provide links to our relatives who have also undertaken DNA testing. It can come as a huge shock to receive mail indicating you have close relatives you don’t know about. You can find more detail about what’s involved in DNA testing here.
Common experiences of people who discover they are donor-conceived as an adult
When people discover they are donor-conceived, they commonly report feeling disbelief, shock, betrayal and anger. It is not unusual to think that there must be some mistake, especially if you have no inkling that your parents struggled with fertility. When donor treatment was first practised, it was extremely common for parents not to tell their children that they were donor-conceived. You can read more information about people’s experiences of finding out they were donor-conceived here.
What can I do next?
Discovering you are donor-conceived can affect many aspects of your life, so it’s important to get support. There are various options available to you. Here are some suggestions:
VARTA has professional and supportive staff who can talk with you about your experience and feelings. VARTA staff can also connect you with support groups and help you decide whether there is anything you might like to do with this new information, either immediately or in future. You can find our contact details here.
Take things slowly
Many people who contact VARTA are feeling shocked, so give yourself adequate time to adjust to the information you’ve received. The time for this will vary between individuals. Don’t rush into any decisions or responses that you may regret in future or that you don’t have the energy to deal with at present. It can be tempting to immediately contact unknown genetic relatives, but these people are strangers. Ensuring you are emotionally ready for the contact is likely to create a better outcome in the long term. It is also possible that if the relative is a sibling, they may, like you, not know they are donor-conceived. If the connection is to the donor, you may not be able to predict how he will initially feel about your approach, particularly if he has not informed his own family he was a donor many years ago. Moving slowly is VARTA’s recommendation even when people have known all their lives that they are donor-conceived. You can read more about what’s involved in donor-linking here.
Speak to your parents
If you have a close and loving relationship with your parents, you may feel able to talk to them about it. Speaking with your parents, who have kept this a secret, can be overwhelming, so it is best to speak to them when you feel calm. Raising the issue in anger can be counter-productive when everybody will have heightened emotions. Writing and or practising what you would like to say to your parents can help prepare you for the conversation. Sometimes when parents are confronted with this information by their child, they panic and deny the information. Parents often experience fear and guilt when this secret is revealed. So having some awareness of how your parents might respond in this situation and being prepared for that can be helpful. Some parents may feel relieved once the truth has been revealed, and over time, this can bring family members closer together.
Apply to VARTA to have the information confirmed
If you were born in Victoria, you can make a Central Register (CR) Application for non-identifying information, which may confirm that you are donor-conceived. It can also alert you to the number of donor siblings you may have. If you want to, you can also apply for information about your donor, including non-identifying information such as hair and eye colour, and identifying information such as your donor’s name, date of birth, and contact details. There is also a Voluntary Register (VR) which can match you to those you are linked to who have also lodged their details and who may wish to connect with you.
Helpful resources & support
If you are a donor-conceived person wanting to know more about your donor and other potential relatives, or a donor who would like to find out about potential offspring, you can contact VARTA first to see if we can link you through our Central Register and Voluntary Register. Parents of donor-conceived people can also contact VARTA for help.
If you were a donor interstate, or conceived as a result of a donor treatment procedure interstate, read more about appropriate bodies that may be able to help you find out more information.
There are a range of support networks and social media groups for donor-conceived people who have found their donors through DNA testing or are still searching.
- DNA Detectives Down Under – Facebook group
- We Are Donor Conceived Website
- Australian donor-conceived Facebook groups
- Melbourne (formerly) Anonymous Sperm Donors (MADmen)
Frequently Asked Questions
What happens to my DNA sample?
Most DTC testing companies send your DNA sample to laboratories based overseas, even if the postal address was originally within Australia. This makes it difficult to determine if the companies’ laboratories are under the same quality control standards as Australian NATA-accredited laboratories which are highly regulated with strict policies for analysis, interpretation and storage of samples.
- Most DTC DNA testing companies retain your DNA sample (you may choose to opt-out if the option is given) and your genetic information until you decide to delete your account.
- In some cases, you may need to specifically request to have your DNA sample destroyed when you delete your personal data.
- Some DTC DNA testing companies may share your genetic information with third-party companies or parent companies.
What questions should I think about before getting testing?
Here are some questions to think about before testing or if you’ve done a test:
- What do you want to achieve out of this process?
- Do you have somebody to support you in an independent, neutral way?
- Have you applied for records that might help you, such as information from VARTA’s donor conception registers?
- Are you aware of all the possible outcomes and have you thought about how you might react to these?
- How will you respond to unexpected contact from a genetic relative?