Identical twins are more likely than siblings or fraternal twins to have the same sexual orientation, although this is not always the case. This suggests that

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Quizplus · Accepted Answer

Genes appear to play a role in influencing sexual orientation, as evidenced by the higher concordance rates among identical twins compared to fraternal twins or siblings. However, the fact that identical twins do not always share the same sexual orientation suggests that genetic factors are not the sole determinant, and other factors, possibly including environmental influences, also contribute to the development of sexual orientation.

Identical Twins Are More Likely Than Siblings or Fraternal Twins