How does a Twin Zygosity Test work?

Identical twins share all of their genes and therefore have identical genetic profiles. Non-identical twins share half of their genes on average, just like a brother and sister, and therefore their genetic profiles do not match perfectly. Genetic profiles do not change with time, so the tests may be applied to identify identical twins at any time throughout their lives.

What is the procedure to get a Twin Zygosity Test done?

A Twin Zygosity Test is generally ordered from Synergene by parents of twins, by the twins themselves or by health professionals on their behalf.

Upon demand, Synergene supplies a free sample collection kit that employs a simple and painless procedure, using a mouth swab to wipe off a specimen of saliva and cheek cells from a subject’s mouth. The collected specimens are deposited in specially supplied packets that may be mailed to Synergene. Alternatively, we also routinely accept specimens in other forms, including blood samples.

At Synergene, the samples are analysed with our state-of-the-art genetic identification system using 16 different genetic markers. Results are available within 5-7 working days after arrival of the samples at Synergene.

What can a Twin Zygosity Test be used for?

There are many possible reasons to have a Twin Zygosity Test. Some examples are:

• Curiosity Testing: Parents of twins and twins themselves may wish to know whether they are identical or non-identical.
  
  
• Medical Necessity: In medical situations requiring blood transfusions and organ transplantation, an identical twin can help save the second twin’s life. Knowing twin zygosity beforehand is thus beneficial for timely action in these occurrences.
  
  
• Medical Research: Twin studies have provided valuable information to the research community. Twin studies help to examine the contribution of environmental and genetic factors in the study of ageing, the study of genetic diseases.

How accurate is the Twin Zygosity Test?

Synergene’s Twin Zygosity Test is extremely accurate as we use 16 different DNA markers to build the genetic profiles. The results guarantee minimum probabilities in excess of 99.99%.

How are samples for a Twin Zygosity Test obtained?

Synergene accepts both mouth swabs and blood samples for Twin Zygosity Tests. The source of the DNA sample does not affect the accuracy and reliability of a Twin Zygosity Test, since an individual’s DNA is the same throughout the body.

Mouth swabs: Synergene supplies sample collection kits for mouth swabs on demand free of charge. Please contact us prior to the sampling appointment to allow adequate time for the kits to arrive. The procedure for collecting the samples is simple and painless, and can be performed easily by following the step-by-step instructions provided. When using these kits it is important to make sure that enough sample is collected. Since collection of these samples is so easy, we recommend sending samples in duplicate to ensure an adequate amount.

Blood: Synergene requires at least 1 EDTA tube (5 ml) of whole blood per donor. The assistance of a medical professional is required to obtain blood samples. The tubes may be stored at room temperature or refrigerated, but the blood must NOT be frozen.

Samples must be accompanied by the appropriate Synergene Submission Form, which is provided with the collection kits or may be downloaded from this web site.

How long does it take to get the results of a Twin Zygosity Test?

Once the sample is received at Synergene, the result is available within 5-7 working days.

Who receives the results of a Twin Zygosity Test?

The results of the test are sent to the individuals designated on the Request Form. No other persons are entitled to these results.