Biology is overrated.

In a society where many people consider adoption an acceptable alternative to old-fashioned procreation, I’m surprised that sperm and egg donors are still seen as “real” parents by a huge chunk of the population.

The recent film “Delivery Man” suggests that blood is thicker than a legal document. Apparently, children need both biological parents in order to become fully functioning, emotionally stable adults. The donor’s right to remain anonymous is overridden by the right of the child to satisfy his or her curiosity.

Even by Hollywood standards, this premise is ridiculous.

First of all, to claim that it takes both biological parents to keep a child from turning into Edgar Allan Poe or a personification of a Radiohead song, is a slap in the face to single parents, adoptive parents, foster parents and same-sex couples. Blood is not everything.

Many children grow up with both biological parents and end up feeling lost and alone.

We all have pain; we all have insecurities. These are not feelings that are exclusive to donor children, no matter how special they may think their circumstances are.

Secondly, if an agreement was made to keep the donor anonymous, the prospective parents and any resulting children should honor that. There should be legal restrictions to protect the donor, because tracking them down and showing up on their doorstep is not cute. It’s an invasion of privacy.

I can understand wanting access to medical history for the sake of the child’s health, but slapping someone with a lawsuit and accusing them of being a deadbeat parent — for sticking to the agreement, no less — is not as funny as Hollywood would like us to think.

It is also unrealistic to assume that a formerly childfree individual will welcome parenthood with open arms after meeting his or her biological children.

Contrary to popular belief, not everyone wants to be a parent. People don’t donate to a fertility clinic or sperm bank to become parents.

They do it so other people can become parents. Financial compensation is supposedly involved.

Are the donor children not satisfied with the parents they do have? Well, tough. No one gets to choose his or her parents.

It doesn’t matter if they were conceived in a cheap hotel room, a honeymoon suite or a fertility clinic. Besides, why open up that can of worms?

If they have personal issues that need to be dealt with, they should consider how they were raised, not how they were made. For all they know, the donor could be a serial killer or a drug addict or Hugh Hefner.

What exactly are they missing by not knowing someone who has no interest in being their parent?