DNA Paternal Analysis Continued'
3. Reporting of Results
Results will be available within 9-14 working days. This will be reported as 0 % or > 99 % for non-matching child and alleged father, and matching child and /alleged father, respectively.
Generation and Interpretation of DNA Analysis Results
We realized the technical complexity of doing DNA analysis. It is our pleasure to discuss with great simplicity of how the results of DNA analysis is reached and reported.
The basis of DNA Paternity analysis assumes a 50 % probability that the alleged father is the father of the child. As mentioned earlier, paternity is determined by searching for an exact matching allele size (gene) of the parent with the allele size of the child.
To interpret the DNA analysis result, there are a few important simplified technical terms to consider.
Allele - a component that carries the genetic information or traits that are contributed by the mother and father, and occupies a specific position in a chromosome. Allele comes in pair which vary in size from one individual to another.
Allele size - a factor that is use in determining whether or not a match exist. This is indicated by measuring the size of the allele in kilobase pairs (kbp). For example, one half of the allele pair from the mother's allele was measured to be 2.75 kbp and the other half was measured at 1.25 kbp. Since an allele is in pair form, one half of allele size of each pair will match the father and the other half of the allele size will match the mother. See Figure 1.
Chromosome - a structure that contains DNA which transmits information. Human beings contains a total of 46 chromosomes contributed by one half from the father and mother.
Gene - the basis of heredity, self-generating and located on an exact position (locus) on a particular chromosome.
Locus - The location of the gene in a chromosome
Paternity Index (PI) - A devise of generating odds (Probability of Paternity - see below) for the alleged father with a matching allele indicating that he is the true father of the child of interest. The PI refers to the specific DNA probe use in DNA locus identification. Additionally, PI vary in odds depending on type of probe use. For example, DNA Probe DC1 with PI 200 and DNA Probe DC2 with PI 30 denotes one out of every 200 and one out of 30, respectively males of same race will have similar allele size.
Calculating Probability of Paternity (PrP)
Formula; PrP (%) = (1/CPI -1) x 100
DNA Probes PI Value
A1 (15) A2 (25 )
A3 (22.5) A4 (60.3 )
Step 1. Multiply the PI Values, CPI; CPI = 15 x 25 x 22.5 x 60.3 = 108,781
Step 2. Plug the CPI value to the equation of
PrP (%) = (1/CPI -1) x 100
Probability of Paternity (PrP) = (1/508,781) -100 = 99.999 %
The Combined Paternity Index (CPI), which is done on a pool base on race is derived from multiplying all of the PI's involved. The higher the value of CPI, the more likely the alleged father is the father of the child. CPI is rated on the following.
CPI Values Rating (Likelihood of being the father) 20-99 low 100-399 moderate > 400 very high
Probe - a fragment from a labeled DNA used as a means of identifying certain locus DNA
Sample DNA analysis report
Dan D. Lion, a refugee from the island of Maldive was the subject of scrutiny for fathering the child of the famous orange orchid flower smeller, Sonia Sampaguita. Dan D. Lion denies the allegations that he ever touched this woman. He asked that his guilt be proven. He agreed to a DNA Paternity analysis.
The participating parties of Hispanic race for DNA Paternity testing include the child, the alleged father, and the mother.
The results are as follows;
Figure 1. DNA analysis result for the child, mother, and alleged father.
Allele pair size (kbp)
DNA probes with corresponding PI values Mother Child Alleged Father DX1, PI 27.5 2.60
DX2, PI 77.3 3.81
DX3, PI 12.5 5.88
DX4, PI 33.5 2.25
According to Figure 1, an allele size match occurs from the mother and child having allele size of 2.60 using DX1 probe, and the alleged father and child having allele size of 4.10 and 4.95 from DNA probes of DX2 and DX3, respectively.
To substantiate the allele size match findings, the following factors of CPI and PrP were calculated.
CPI = 27.5 x 77.3 x 12.5 x 33.5 = 890,157
Probability of Paternity (PrP) = (1/890,157 -1) x 100 = 99.999 %
In conclusion, the alleged father is 99.999 % probable and 890,157 times more likely to be the true biological father of the child as compared to a non-analyzed random male of equal race.