Studies of twins, both identical and fraternal, suggest that heredity is one of the major factors in determining a person’s sexual orientation. In fact, many studies say genetics swamps other ...

Boy-girl twins are always fraternal. A boy-girl pair may be identical with a rare genetic mutation, but this brother and sister are like regular siblings born together. Can fraternal twins look ...

Credit: QIMR Berghofer Medical Research Institute "It has long been known that fraternal twins have a genetic basis, with non-identical twins often running in families. However, identifying the ...

Twins are fascinating and are the subject of many old wives tales. If you have a set of twins in your family, a relative may have told you that you have a higher chance of having twins — but do ...

We have always been asked whether we are fraternal or identical twins. While this question isn't weird, people's insistence on genetic impossibilities can be a bit strange. Countless times ...

The greater resemblance between identical twins than between fraternal twins is consistent with the view that genetic factors influence the behavioral characteristic or physical trait under study. Of ...

If identical twins are more likely to share a condition than fraternal twins are, then this indicates a genetic component, which is the case in studies on depression. While twin studies suggest ...