Category:
Twin Zygosity DNA Testing
Identical twins can be born as either boys (XY) or girls (XX). They are always the same gender, but it’s more common for them to be girls (XX) than boys (XY).
Identical twins can be born as either boys (XY) or girls (XX). They are always the same gender, but it’s more common for them to be girls (XX) than boys (XY).