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Twin Zygosity DNA Test

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$109 – One Day Results

Twin Zygosity Explained

Twin Zygosity Test - 100% Accurate

Zygosity is about the genes in twins. Science confirms two twin types: identical and fraternal. There might be a third type, half-identical or polar-body twins, however this isn’t proven yet. This could explain why some fraternal twins look alike. Only DNA testing can only show if twins are identical or fraternal.

Identical twins form when a single egg splits into two, known as monozygotic. Fraternal twins result from two eggs and two sperm, known as dizygotic. Observing twins doesn’t reveal their type, only a Twin Zygosity DNA test can do that.

This DNA test is a simple and painless test that analyzes the DNA of each twin to determine whether they share the exact same DNA. Identical twins will always have the same DNA profile. Monozygosity is the scientific term for identical siblings. Fraternal twins, referred to as dizygotic, will have different DNA profiles, just like any other siblings.

How Accurate Is a Twin Zygosity Test?

Our Twin Zygosity Test Kit guarantees 100% accuracy, and you can perform it at home. Your results are ready in just one business day after the lab has the DNA samples.

If you want to learn how we create a person’s DNA profile, you can click on How A DNA Test Is Done.

Twin Testing Can Help Settle Questions

You get the following benefits with a Journey Genetic Testing Twin Zygosity test:

  • Peace of Mind: Our zygosity test can provide a “Yes” or “No” answer about whether those who submit DNA are identical or fraternal twins.
  • Medical Insights: Identical twins are more likely to share the same genetic disorders than fraternal twins. If one twin is diagnosed with a genetic disorder, the other twin may also be at risk.
  • Personal Identity: Discovering zygosity contributes to a sense of identity, highlighting the uniqueness or shared genetic traits between you and your twin.
  • Assess Future Possibilities: There is an increased probability of conceiving twins again for women who have had non-identical twins.
  • Great Gift Idea: A Twins DNA Test is also a unique gift idea for multiple birth parents or their children.

How Much Is A Twin DNA Test Kit?

 Our Twin Zygosity test is $109. Everything you need is included:

  • Rush shipping of your Twins DNA Test kit with a USPS tracking number.
  • Complete, easy-to-follow instructions on how to take collect the DNA samples.
  • A pre-paid overnight FedEx label to send your samples to our lab.
  • Two DNA sample collection swab packages, containing two sets of swabs (4 total) in each package
  • Email your 100% accurate results in 1 business day after all DNA specimens arrive in our lab.

If you need to test more siblings (triplets, quadruplets), you can choose this option while placing your order.

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FAQs About Twin DNA Testing

Is A Parents DNA Sample Needed To Do A Twin Zygosity Test?

No. The testing is done only using the DNA from the twins. The results will be 100% accurate.

Do Twins Always Have The Same Father?

The answer may surprise you! While identical twins always have the same biological father, fraternal twins can have different fathers. This can happen if a woman has sexual intercourse with two different men around the same time when both embryos are conceived. While it is not common, we have seen this happen several times over the years.

Do Identical Twins Have The Same Blood Type?

Identical twins almost always have the same blood type. We say almost because we have seen an extremely rare exception. In contrast, fraternal twins can either have the same blood type or different blood types.

My Twins Had Separate Placentas. Doesn’t That Mean They Are Fraternal?

Twins with separate placentas aren’t always fraternal. To know for sure, you need a twin zygosity DNA test.

Before DNA testing became common, doctors and parents believed that if twins had their own amniotic sacs and placentas, they must be fraternal.

Fraternal twins begin when two different sperm fertilize two separate eggs. These fertilized eggs grow separately in their own ‘in-utero homes’ and can be girl/girl, boy/boy, or boy/girl.

Identical twins begin when one fertilized egg splits into two. This usually occurs around days 4 or 5, after the placenta and amniotic sac have already started forming. However, if the fertilized egg splits before the placenta and amniotic sac usually begin forming for identical twins, like around days 2 or 3, each zygote grows its own sac and placenta.

So, what might seem like fraternal twins to a doctor may actually be a pair of identical twins.

Does A Mother’s Age Affect Twinning Rates?

Typically, older women have a greater likelihood of conceiving twins compared to younger women. A woman who is 35 years old is four times more likely to have fraternal twins. As women approach menopause, they undergo hormonal changes, leading to an increase in their follicle-stimulating hormone levels.

What Is A “Mirror” Twin?

The phrase “mirror twin” describes a unique category of identical, or monozygotic, twin pair. These twins look like they’re looking in a mirror because their special traits, like birthmarks, dominant hands, or other features, are on opposite sides.

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