What Is an NPE? What You Need to Know!

What Does NPE Mean? 

The acronym NPE stands for Non-Paternal Event, or Non-Parental Event. Some people prefer the term Misattributed Paternal Event, or Misattributed Parental Event (see Concepts: What are NPEs and MPEs? | DNAeXplained – Genetic Genealogy (dna-explained.com)).

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NPEs can also be referred to as Not Parent Expected, ‘paternal discrepancy’, non-parental events experience, false paternity, non-patrilineal transmission, or ancestral introgression.

Genetic genealogists consider NPE to be an event that causes a break in a hereditary surname and the Y chromosome (see Trauma, Non-Paternal Events (NPEs) and Recovery – Transforming Trauma).

Whatever term is used, an NPE is a situation where the wrong man has assumed paternity. 

The term could be applicable due to adoption, a donor situation, cheating and adultery, any situation where a mother has a child with someone other than her husband or the child’s primary caretaker or where lies or deception prevent a child from knowing who his or her real father is.  

Typically, in adoption or step-parent situations, the key individuals know that the step or adoptive parent is not the biological parent.

If it was not discussed or known then, prior to official birth certificates and when adoptions were not documented, the terms ‘undocumented adoption’ or ‘unknown parentage’ were difficult to ratify. 

Testing For NPE 

DNA testing can, nowadays, resolve many NPE situations that were not resolvable in the past. 

DNA testing and DNA matches are the only aspect of autosomal DNA that can provide evidence of an NPE or dispute it. Ethnicity estimates cannot be used to determine paternity.

Experts in genetic genealogy perform studies using autosomal DNA to determine whether or not the known family tree matches the DNA results. If data that shows the expected range of shared DNA between relatives of a particular relationship type doesn’t match up, NPE may have occurred. 

Some researchers focus on male lines of family trees, since men generally carry their expected father’s surnames. 

Y DNA testing is used to verify haplogroup and Y DNA matches.  

Frequency Of NPEs 

According to What is a NPE? – Who are You Made Of?, the average rate of NPEs is less than 10%, and no higher than an average of 4%; only about 1 in 25 births

The frequency of NPEs can vary across time, culture, and geography. Access to court orders, having the wherewithal to get DNA testing and legal assistance may vary significantly between social strata and communities. 

High paternal confidence means that the father believes he is the biological father of his child. Where this is the case, there’s a much lower percentage of NPEs; about 1.7%, or less than 1 birth out of 50. 

Low paternal confidence means the father feels there’s a good chance that he’s not the biological father. In these cases, NPE rate can be as high as 30%.  This isn’t surprising, since a lot of people who do the DNA testing would have low paternal confidence. 

Emotional Aspects Of NPE 

As I’m sure we can all imagine, the emotional toll of an NPE situation can be immense for the child concerned, the legal father, the biological father, and the mother.  

According to Trauma, Non-Paternal Events (NPEs) and Recovery – Transforming Trauma, NPEs result in a child experiencing grief and confusion, changes in the family dynamic, and possible identity crisis.  

Due to tribal ancestry and evolutionary psychology, humans seek connection with others and when our sense of community and family is upset, feelings of rejection can emerge.

Being rejected from a tribe or community meant certain death to our evolutionary predecessors and that primal fear is still within us. If the child lacks coping mechanisms, trauma results. 

See The Legal Ramifications of Paternity | Law blog online 

Any paternity issues, including NPE issues, are handled by Family Law courts. 

The legal father of a child has legal rights and responsibilities regarding the child. This is regardless of whether he is the biological father.  

When a child is born to a married woman, the legal father is the husband and he’s assumed to be the biological father. If at any point during childhood, another man, not the husband, believes he is the father, he can file a paternity action in court. 

When a child is born to an unmarried woman, paternity has to be established voluntarily or by court order. Legally speaking, a name on a birth certificate does not establish paternity. 

Unmarried parents can establish paternity of their child voluntarily at any point by signing a ‘Voluntary Acknowledgment of Paternity’ form, acknowledging that the man signing is the child’s legal father.

For sixty days after signing, either parent has the right to revoke it, proving that extreme force or fraud was used. After sixty days, it becomes legally binding. 

In cases where the voluntary form is not signed, the mother, the man who thinks he is the father, the child, or Child Support Services can seek a court order. The court will order a genetic test for the mother, potential father, and child.

A court order can be submitted before the birth of a child, but the test won’t be administered until after the child is born. 

A mother and father can get a paternity test for a child before getting their marriage license.  

A biological father, who is not the legal father, can take a paternity action to establish himself as the legal father.  If the court finds that the legal father is not the biological father, the court will decide whether the legal or biological father is the best option in the interests of the child. 

Financial Aspects Of NPE 

Paternity determines child support orders, and other financial assistance for the child. Alleged fathers may provide health insurance benefits and other support to the child, the child may be entitled to certain government benefits from their father, such as disability or military benefits, and the child is entitled to estate inheritance from their father. 

Paternity cases can cover a range of topics, such as the establishment of child support, child dependency for taxes, medical expenses, pregnancy expenses, birth certificates, and more. 

If a man believes he is not the father of a child, he can contest things like child support by first pursuing a paternity action. 

Social Aspects Of NPE 

Men who want to play an active part in their child’s life may need a paternity test for court orders concerning child custody and visitation rights.  

Paternity rights relate to custody, visitation, parenting plans, parental responsibility and similar, as well as the more financial support rights of the child.  

Complications Of NPE 

Complications can arise because of the putative father registry, paternity actions, court orders, sperm donor cases and the disestablishment of paternity. It may not be possible to obtain a DNA sample from the suspected biological father. Without a DNA sample DNA testing cannot occur.

There may have been many deceptive actions taken to keep the identity of a biological father secret and trying to unravel a web of deceit can be very difficult. There may be vested interests in keeping the secret. Involving the courts costs time and money. 


Ideally, we’d all like it if our biological father was our legal father and married to our mother. In this scenario, the rights of the child and the rights and responsibilities of the parents are clear and acknowledged and the child should hopefully be secure and able to get on with enjoying childhood. 

Unfortunately, human relationships are often very complicated and entwined with emotional and practical attributes. The man who fathered a child biologically may not be the man who considers himself the biological and legal father of the child.

A mother may not always be sure who is the biological father of her child. If she’s married during conception but has another lover extra-maritally, then the NPE issue affects two men.  

With the advent of DNA testing, it is much easier than it was in the past to establish biological paternity. All is well if biological and legal paternity coincides but when they don’t it becomes a matter for the courts to decide. In the end, the child is of primary concern because the welfare of the child has to come first. 

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