Since blood type of a child is inherited by the parents, it can be used to disprove paternity in some cases. For instance, if a mother's blood type is AB and her child's is also AB, then the child's father must be either A, B or AB. Therefore, if an alleged father is type O, he can be excluded as being this AB-type child's father. On the contrary, however, blood type is not a reliable method of proving paternity. Since a person can have only one of four different blood types, it could be very possible that two alleged fathers of a child actually have the same blood type, say A-type for the case described, but only one will obviously be the child's father. In this case, only a DNA paternity test could accurately determine which man must be the child's father.



The following list describes the expected blood type for the father, when the mother's and child's blood types are known. The letter/letter combination following ?Mother, Child and Father? indicates the blood type, A, B, AB or O.

* Mother A + Child A = Father A, B, AB or O

* Mother A + Child B = Father B or AB

* Mother A + Child AB = Father B or AB

* Mother A + Child O = Father A, B or O

* Mother B + Child A = Father A or AB

* Mother B + Child B = Father A, B, AB or O

* Mother B + Child AB = Father A or AB

* Mother B + Child O = Father A, B or O

* Mother AB + Child A = Father A, B, AB or O

* Mother AB + Child B = Father A, B, AB or O

* Mother AB + Child AB = Father A, B or AB

* Mother O + Child A = Father A or AB

* Mother O + Child B = Father B or AB

* Mother O + Child O = Father A, B or O

Not Our Father's Children

When many people think of a DNA test, they may envision a desperate mother trying to figure out who her child's father could be. In many cases, yes, DNA testsare used to resolve doubts. However, now that DNA testing has been recognized as having so many applications and is so widely available to the public, many people are taking part in tests for reasons other than verification of paternity. Ironically, though, some people have uncovered hidden truths of non-paternity. Adult siblings trying to map their ancestral lineage have actually found out that they have different fathers, when it was never a question that they might. Parents of children with rare genetic disorders, who must both carry a gene for their children to inherit the disorder, find that the ?father? actually is not a carrier. There are other scenarios where people not seeking to establish paternity, actually discover non-paternity issues. So, obviously non-paternity is not restricted to those people who undergo DNA paternity test. And, as science and DNA testing continue to advance and become more commonplace, more and more people may uncover unexpected family secrets.

The DNA Identity Testing Center of Bio-Synthesis, Inc. is an active member of the AABB Relationship Testing Accreditation Program and actively participates in proficiency testing by the College of American Pathologists. With nearly 15 years experience in the DNA testing field, law enforcement, legal representatives and individuals alike trust BSI with their private and legal DNA testing issues, worldwide. Visit www.800dnaexam.com for a full description of all testing services.