Special DNA Tests - Twin Zygosity DNA Testing

Twin siblings can be either 'fraternal' or 'identical'. Our Twin Zygosity DNA Test is designed to determine if twins are fraternal or identical.

Click here to order your Free BIOSWAB^TM DNA Collection Kit or contact our DNA Specialists at DNAtest@800dnaexam.com or 800-DNA-EXAM.

	Identical Twins
	Fraternal Twins

Special DNA Tests - Twin Zygosity DNA Testing

Identical twins occur when a single egg is fertilized with a single sperm and splits very early during development. Each division contains the exact same genetic potential.

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 occur when two sperm fertilize two eggs. In this case, the amount of DNA in common between the twins is generally comparable to that of full siblings. Furthermore, if the two sperm cells originated from two different men, then the twins would represent half-siblings. Additionally, physical attributes may not be similar, and they also may not be of the same sex.

Interpretation
After testing the samples, a DNA profile for each twin will be established. If the profiles are different, then the twins are fraternal, and if the profiles are identical, then the twins are identical. Results are available within 5-7 business days after samples have reached our laboratory.