DNA Paternity Testing 

A DNA paternity test is a test that will test and verify if there is a biological relationship between two people. The individuals involved are a child and an alleged father.

How is a DNA Test Performed?

 Paternity Tests provide you peace of mind or it could also be used for legal requirements like child support, inheritance, immigration, forensic cases and medical cases. Each child inherits 50% of the father’s DNA and 50% of the mother’s DNA. This makes it possible to trace the relationship between alleged father and child. If the DNA markers are not present, there is no relationship. If there are markers, the level of relationship will be indicated to a document at 99.999% accuracy. The procedure for a DNA test is a simple and accurate process. A cheek swab, buccal swab) is taken from each individual, i.e., the alleged father and the child. The samples are then analyzed to determine if there are sufficient markers in the DNA samples.

SmarTest Labs performs these DNA tests under a strict chain of control. We are sensitive to the needs of the individuals providing the buccal swabs, as many life-changing decisions are made from these results. We serve the Maryland, WA, DC, and VA areas. 

Can Paternity Testing be Done Between Brothers?

The answer to this question is “yes,” this is possible. The DNA from each of the brothers is taken and compared to the child or the DNA will show a relationship between the 2 individuals.

Relationships between 2 individuals can take on a variety of scenarios.

  • Siblingship – This is when verification is required to show that the two individuals are brothers. This is possible and very accurate as if the DNA markers match, then they have the same father. Each person has 50% of their DNA from their father and 50% from their mother. At SmarTest labs, we are able to separate the DNA of the mother and father of the two individuals. We then compare the fathers’ DNA of both to see if there is a match.
  • Twins – This test is more complex if it is a test for identical twins. Identical twins have approximately 100% of their father’s DNA matching. It is important to let your testing organization know that the individuals are identical twins, as the process will be handled differently.

If two individuals are related and have 50% of their DNA match, it is also true that 50% of their DNA could be different. This will provide the scientists with enough information to determine paternity. The individual with the matching DNA markers will be the person who is related to the child. The other alleged father who does not match DNA markers will not be the father.

What are Some of the Advanced DNA Tests?


  • Twins can either be fraternal (dizyogotic) or identical twins. This difference will determine paternity testing outcomes.
  • For non-identical twins with 50% of each parent’s DNA, the testing for paternity relationship is the same as other paternity tests.
  • For identical twins who have identical DNA, the test for paternity will not be able to distinguish which twin was the father of the child. It will only determine that one of them is the father of the child.


  • If two individuals are alleged fathers but are also cousins, they can be tested for paternity. Cousins have a DNA linkage of about 13%. Because the DNA between cousins is lower, it will be easier to link the DNA markers in a paternity test.
  • SmarTest Labs will provide you guidance in all your decisions regarding the testing required. Our testers are trained, certified and skilled at explaining the necessary tests that fit your needs.

Paternity DNA Test for Father and Son

If there is a need to test both a father and a son, a DNA paternity test can be done with great accuracy. The father and son share 50% of their DNA. The rest of the 50% is not a match between a father and son. SmarTest labs scientists are able to use the non-match 50% DNA to determine which individual is the father of a child.

It is important that you inform SmarTest Labs of the relationship between the individuals when the test is ordered. This will help guide you through the testing process.

What is a Y Chromosome Test?

A Y-Chromosome test (Y-STR) will trace the lineage of a father and his ancestors. The Y-STR DNA test looks at the Y chromosomes. The Y-STR DNA markers include short tandem markers, which vary from person to person. Each of the reptations is also known as markers. These markers will indicate a relationship or non-relationship in a paternity ancestry test. STR markers provide a personal haplotype. This, in turn, will indicate the haplogroup and which group and individual falls in. A single-nucleoid polymorphism (SNP) reflects a change to a single nucleotide in a DNA sequence. These changes are very low and help to retain the DNA through the different ancestries. This, in turn, helps trace ancestral connections between the male ancestry tree.

What is a Mitochondrial DNA Test?

Mitochondrial DNA (mtDNA) is the process of tracing DNA between the maternal lineages. mtDNA will trace relationships between mothers, sisters, maternal grandmothers, aunts, and uncles. Mitochondrial DNA tests will show a very close relationship between related individuals. Due to this, it is a great asset in tracing people, especially if they have been separated from their families for any reason. mtDNA does not degenerate easily as it has a circular structure. This structure insulates the DNA from enzyme or nuclear degeneration. The mtDNA test helps trace accurately the relationship between a maternal ancestry line. Mitochondrial DNA is used in research and by the government to validate biological relationships.

How Accurate is DNA Testing?

Paternity tests done at reputable labs like SmarTest Labs are highly accurate. We follow a strict chain of custody, and all our testers are trained in the technical skills of testing and the selection of the right and appropriate test for a customer. All tests are not the same and SmarTest Labs customizes after listening to your requirements. Tests that are done with an accredited lab and under strict controls will provide you with 99.999% accuracy if there is a positive match and 0% if there is a negative match. The accuracy of the outcomes is important as these could cause life changes. However, if samples (non-legal) are collected by the donor themselves, they can contain contaminants. The process of collection & transmission of the samples is a science in itself and must be done with great care. It is best done by trained individuals for accuracy in outcomes.

Fraud is always something that will always be present. Intentional deception of results, gathering of samples and swapping of samples will cause the results to be inaccurate. A good lab will be able, at times, to pick up on the potential of fraud. It is important to get your tests at an accredited lab for accurate results.

Smartest Labs is an accredited AABB-certified lab that will provide you with accurate results and appropriate guidance on your DNA testing. We are located in the Maryland, WA, DC, and VA areas and serve the population in that area.