Determining fatherhood by blood type

Can I determine paternity by blood-type?

One of the most often asked questions about determining paternity concerns blood tests and blood types. Unfortunately, there is also a great deal of misinformation about the validity of using this method.

You can only eliminate potential fathers using blood type some of the time. You can never prove that a man is the biological father using blood typing. Unlike a DNA test, most of us could only narrow our potential fathers down to 1 of a few billion men using blood type information alone.

Blood type is genetic

The A and B antigen molecules on the surface of red blood cells are produced by two different enzymes. These two enzymes are encoded by different versions, or alleles, of the same gene: A and B.

The A and B alleles code for enzymes that produce the type A and B antigens respectively. A third version of this gene, the O allele, codes for a protein that is not functional and does not produce surface molecules. Two copies of the gene are inherited, one from each parent. The possible combinations of alleles produce blood types according to the diagram on the right.

The table above is provided as a courtesy and should be used for general information only.

Please note that blood types alone CANNOT be used to determine paternity with a conclusive result. Blood types can only provide a possibility of fatherhood, never a definitive answer. A Bio-Gene DNA Paternity Test is the most reliable means of identity verification of the biological father.

Bio-Gene DNA Testing does not provide consultation services pertaining to blood types. If you have questions concerning your blood type please visit with a medical provider of your choice.

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