TWIN ZYGOSITY TESTING new york, we love new york

It can be difficult to tell whether twins are identical or fraternal. Fraternal twins of the same sex may have very similar features, while identical twins can have distinct physical features that enable others to easily differentiate between them. A twin zygosity test can quickly reveal with certainty whether twins are fraternal or identical.

We compare the twins’ DNA profiles - identical twins will have exactly the same profile.

Determining Twin Zygosity

At birth, identical twins share one placenta, while fraternal twins have separate placentas. However, the placenta may be damaged during the birthing process, so that the doctor cannot determine twin zygosity. Many adults may also take the twin zygosity test - their medical records might have been lost, or some twins may have been separated at birth. In such cases, a twin zygosity DNA test is the most precise and convenient test and indeed the only option.

Health Implications of Twin Zygosity
Many patients take the twin zygosity test just to satisfy their curiosity. There are other health benefits from taking the test. Knowing your complete medical history, including twin zygosity, is always important in the prevention, diagnosis, or treatment of disease. Identical twins are also perfect organ donors for each other, should such a need arise.


Tested Parties
In a twin zygosity test, only the twins need to be tested. Twin zygosity testing compares the DNA of two twins to determine whether they are identical or fraternal. Identical twins are identical in every way, including identical DNA. Hence, it can be conclusively determined if twins are identical.

Identical Twins
When one egg is fertilized by one sperm cell, and then divides and separates, two identical cells will result. These cells will then develop into identical twins. The DNA profiles for identical twins will be identical. Additionally, the physical attributes of identical twins will seem similar for traits such as hair color, hair texture, eye color, height, and weight. They must also be of the same sex.

Fraternal Twins 
When two eggs are independently fertilized by two different sperm cells, fraternal twins result. The DNA profiles for fraternal twins will not be identical, and they are just like full-siblings that are born at different times. Furthermore, if the two sperm cells originated from 2 different men then the twins would be like 2 half-siblings. Additionally, the physical attributes of fraternal twins may not seem similar for traits such as hair color, hair texture, eye color, height, and weight. They also may not be of the same sex.

The Twin Zygosity DNA Test is used to establish DNA profiles for the twins being tested. If the profiles are different, then the twins are fraternal, and if the profiles are identical then a probability of being identical twins is calculated. Results are available in 7-9 days after specimens have reached the laboratory.

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