Twin Testing

Are they Genetically Identical?

One in every seventy births produces twins.  As children, they are usually raised together and share a very similar environment as they grow up.  But one third of all twins born share much more than this – identical twins have exactly the same genes.

DNA testing for Twins

Fraternal Twins

Fraternal twins are the result when two different eggs (ova) are fertilized by two different sperm. This leads to the development of two separate placentas.  Fraternal twins are more common than identical twins and account for about 2/3 of twin pregnancies.

Identical Twins

Identical twins develop when a fertilised egg splits. Depending on when the split occurs will determine if the twins share a placenta or if they each develop their own placentas. In general, the later the split occurs, the more likely that the twins will share one placenta.

If it is important to know if they are identical or if you are just curious, we can provide the answer.

The Process

A mouth swab sample is collected from each of the twins (or triplets, quads etc). Samples can be collected at home.

DNA is extracted from these samples to obtain a genetic profile of each individual. Identical (monozygotic) twins have exactly the same genetic profile.

Non-identical (di-zygotic) twins have a different genetic profile and are therefore no more closely linked genetically than with other siblings.

The Cost

The cost to test both children to determine if they are identical is $176.