Of course, we need first to determine how 'right' is defined in this case. The direction of the right is also important. If it is a right to know one's biological origins, what are the rights of those originators/progenitors to privacy?
An excellent question and I look forward to the debate!
Indeed an interesting question. I would consider it a basis human right to have access to that knowledge (of who are one's biological parents). However,if for instance, a lesbian woman has artificial insemination, the full details (of the sperm donor) are - to my knowledge - often not revealed (in South Africa, at least). I do not regard gender and LGBT rights in any way at stake if adoption or a.i. must guarantee that the adoptee or 'own' child has access - at some point of her life - to knowing who her biological parents are.
Obviously, it can occasionally be important to know whether a particular person happens to be your half-sibling.
That leads to the question of how feasible it might be to try and enforce a law or decree insisting that such information should always be available; i.e., making it a crime to refuse to provide full details of a child's parentage. In the face of such a legal requirement, there will sometimes be deliberate evasion, and even lying. Indeed, there will also be instances when a woman could state quite truthfully that "she does not know"!
Napoleon swung the other way, forbidding all attempts to challenge and investigate paternity - (even without the advanced biochemical resources and techniques which we enjoy today).