Analysis of paternity testing results by Identifiler system in Thailand

Abstract

One of the applications of Identifiler ™ system is to use for paternity testing. This study aims to analyze the paternity testing results of trio and duo cases. A total of 500 paternity cases were divided into 120 trio and 380 duo cases. Combined paternity index (CPI) and power of exclusion (PE) were calculated for inclusion and exclusion results. Based on statistical analysis, the lowest CPI value obtained from trio cases was 1,340.89 with a probability of paternity more than 99.92%. In duo cases, the lowest value of CPI was 32.18 with a probability of paternity higher than 96.98%. Moreover, we noticed that approximately 50% of the CPI values in trio and duo cases were in a range of 10 6 –10 8 and 10 4 –10 6 , respectively. For exclusion results, D2S1338 had the highest PE value in trio cases (81.20%). In duo cases, D8S1179 showed the highest PE value (75.80%). TPOX had the lowest PE value in both trio and duo cases (29.10% and 24.60%). The minimal numbers of excluding loci were 7 and 3 in trio and duo cases, respectively. In addition, this study showed that a threshold value for CPI should be greater than or equal to 1,000.