@123bananas
Unmarried fathers legally have parental responsibility if they are named on the certificate, it wasn't the case until sometime in the last decade or so.
I think the Birth certificate is generally used to ascertain parental responsibility. This is fallable too... The unmarried father on my dd1's birth certificate is NC with her and was abusive to me so generally I would want to wipe away his assumed 'parental responsibility' that he has gained by default. So to me, the birth certificate doesn't mean much, really.
With scientific advancements, surely any genetic history that a person might need to know will be easy to ascertain in the not toi distant future?
I guess it depends how much value you hold in a birth certificate and the words on it.