What Happens If My Paternity Test Results Are Inconclusive?

Receiving inconclusive paternity test results can be frustrating and anxiety-inducing, especially when you were expecting a clear yes or no answer. An inconclusive result means the laboratory could not determine paternity with sufficient statistical confidence to issue a definitive inclusion or exclusion. This outcome is uncommon, occurring in roughly 1 to 3 percent of standard paternity tests, but understanding why it happens and what options are available can help you move forward quickly toward a definitive answer.

Why Inconclusive Results Occur

Several factors can lead to an inconclusive result. The most common cause is degraded or insufficient DNA in the submitted sample. If the buccal swabs were not collected properly, were contaminated with food or drink residue, or were exposed to moisture during shipping, the laboratory may not be able to generate a complete DNA profile. When key markers cannot be read, the statistical calculation lacks enough data points to reach the confidence threshold, which is typically a combined paternity index of 99 percent or higher for inclusion. Another cause is a genetic mutation at one or more marker locations, which can create an apparent mismatch even when the tested man is the biological father. Mutations occur naturally and are observed at approximately 1 to 2 percent of tested loci.

The Difference Between Inconclusive and Exclusion

It is important to understand that an inconclusive result is not the same as an exclusion. An exclusion means the tested man is definitively not the biological father because the DNA profiles are incompatible at multiple markers, typically three or more. An inconclusive result means the data is ambiguous and the lab cannot confidently go in either direction. In mutation cases, the tested man may show a mismatch at only one marker while matching at all others. The laboratory will typically flag this as requiring further analysis rather than issuing a false exclusion, which is the responsible and scientifically correct approach.

Retesting Options and Extended Analysis

When results are inconclusive due to sample quality, the simplest solution is to recollect and resubmit samples. Most reputable laboratories offer free or discounted recollection kits when the original samples were inadequate. When the issue is a possible mutation or the alleged fathers are biologically related, the laboratory may recommend testing additional STR markers beyond the standard panel. Extended panels of 35 to 46 or more markers provide significantly more statistical power and can resolve nearly all inconclusive cases. Adding the biological mother's sample to the analysis is another highly effective strategy, as it allows the lab to definitively identify the maternal contribution and isolate the paternal alleles for clearer comparison.

How Laboratories Handle Mutations

When a single-locus mismatch is observed, laboratories apply established scientific protocols for mutation analysis. They calculate a paternity index that accounts for the known mutation rate at the specific locus where the mismatch occurred. If the mutation-adjusted combined paternity index still exceeds the reporting threshold, the laboratory can issue an inclusion with a note explaining the mutation. If the index falls below the threshold, additional testing is recommended. The American Association of Blood Banks (AABB) and the International Society for Forensic Genetics (ISFG) have published guidelines that all accredited laboratories follow for handling mutations, ensuring consistent and scientifically sound interpretations.

Steps to Take If Your Results Are Inconclusive

If you receive an inconclusive result, contact the testing laboratory directly to understand the specific reason. Ask whether the issue was sample quality, a potential mutation, or an insufficient number of markers. Request a detailed explanation of your options, including recollection, extended panel testing, and adding the mother's sample. Before retesting, review the sample collection instructions carefully to ensure optimal DNA quality. Avoid eating, drinking, or smoking for 30 minutes before collection, rub the swab firmly for the full recommended duration, and allow swabs to air-dry completely before sealing them. If you want a quick preliminary indication while waiting for retesting results, the TrueDadz AI facial analysis at $14.99 can provide an independent data point based on facial resemblance patterns.

Affiliate Link

Need a Legal DNA Paternity Test?

If you require court-admissible results or definitive genetic proof, scan the QR code or click below to order an accredited DNA paternity test from a certified laboratory.

Order a Certified DNA Test