Twin DNA test

Twin DNA Test (Zygosity Test)


  • Ireland’s fastest DNA zygosity test
  • Just €139 for results in 2-3 days
  • 100% confidential service
  • Award-winning, accredited laboratory

Four easy steps for your DNA zygosity test

Buy your collection kit

Collect your cheek cell DNA samples

Post back to our laboratory

Receive your results by email

Zygosity twin testing

A twin DNA test is used to establish whether multiple children from the same birth (such as twins, triplets, quadruplets, etc.) are genetically identical or not. Identical siblings are monozygotic, which means they were formed from a single fertilised egg that went on to split into separate embryos.

Monozygotic twins have the same DNA. Twins that are non-identical from the same birth are known as dizygotic; triplets are trizygotic; quadruplets are quadzygotic; and polyzygotic is the umbrella term for multiple zygotes. These siblings resulted from separate fertilised eggs and share DNA in common, just like siblings from different births.

Why would you need a zygosity twin test?

Siblings that are of different sexes are not identical. By around 2 years of age, zygosity of same-sex twins may be quite clear from their physical features. Growth patterns (such as hair and eye colour, hand and feet appearance) can indicate whether or not the children are identical.

It can be interesting to know whether multiple siblings are identical because it may have been unclear in utero. Identical twins don’t always share the same placenta and sac: it all depends on when the eggs splits. Parents would be interested to know this information, and sometimes the twins themselves like to know when they’re older.

Establishing whether multiple siblings are identical can also help assess the likelihood of conceiving twins again: there is an increased risk for women who have had non-identical twins. In addition, some illnesses may affect monozygotic children so you could establish whether both/all children need testing for a particular condition.

Another novel use of a DNA zygosity profile, and which is increasingly in demand, is as a unique gift idea for multiple birth parents or their children.

Just €139 for results in 2-3 days

How do we do our twin testing?

Our in-house laboratory uses the most up-to-date testing technology to ensure the reliability of our DNA tests. We offer accredited DNA testing (up to 45 markers) and retest all our exclusion results to ensure accuracy.

Your DNA zygosity test kit is sent direct to an address of your choice using discreet packaging. The kit includes mouth swabs to obtain tiny amounts of DNA from inside each sibling’s mouth. The swab is rubbed gently and painlessly on the inside of the cheek. There is no need to worry about needles.

We examine specific markers present in repeat sections of DNA from each sibling. These Short Tandem Repeat (STR) loci include the Amelogenin (gender) locus. The DNA seen at each of these STR loci is compared between the tested siblings to determine zygosity: monozygotic twins will share the same DNA profile whereas dizygotic twins will have different DNA profiles. A DNA profile is produced for each of the samples provided.

Order Ireland’s fastest, most accurate twin DNA test online now for only €139 with results in 2-3 days*.

*working days from when the samples arrive at our laboratory before 10am

What is the difference between the standard and the enhanced test?

Our standard twin test is already industry-leading, as it analyses 25 DNA markers (the industry standard only analyses 16-21 markers).

What makes AlphaBiolabs unique is that we can also analyse up to 45 DNA markers. This allows more genetic material to be analysed, which strengthens the result and provides additional reassurance.

This is ideal for customers who want the most powerful DNA test available. 

What’s in our DNA twin testing kit?

Our DNA zygosity testing kit contains enough collection swabs to test two siblings. Extra swabs can be added as required.

Our home zygosity test kit is designed to be user-friendly with easy-to-understand instructions on how to take your test samples and return them back to our laboratory.

If you have any questions or do not understand how to take your samples please get in touch on 0140 29466. We will be more than happy to talk you through the process.

Order the fastest twin DNA test in Ireland, from our award-winning laboratory

Order a DNA twin test today and you will receive:

  • Peace of Mind DNA zygosity test request/consent form
  • Full instructions on how to take the DNA zygosity test and return the samples
  • A self-addressed envelope to send your DNA samples back to us
  • Two DNA sample collection swab packages containing two swabs in each
  • Individual test sample envelopes for two siblings
For 26 years we believed that our twin boys were non-identical, as confirmed by the gynaecologist during the scan, which showed that they were in two separate sacs and that there were two placenta present.

All through their lives people struggled to tell the boys apart and we decided to arrange a zygosity test with AlphaBiolabs to clarify the matter once and for all. To our surprise the results confirmed that the boys are identical. This has ended years of speculation within the family and has provided us with conclusive scientific proof. Gail and Chris Evans

Buy your zygosity testing kit here today

Buy the fastest, most accurate Twin DNA test here