Evaluation of diallelic STR markers with inter-population allelic database for their usefulness in paternity trios in the Central Indian population

Abstract

Background

Most of the forensic DNA laboratories have migrated to new generation STR kits of 6 dye chemistry with more than 20 autosomal STRs. The population-specific databases of such STR markers are lacking in many regions.

Aim

To evaluate the effect of the inter-population database in 100 paternity trios with no inconsistencies at 23 STRs.

Subjects and methods

100 paternity trios were evaluated considering inter-population allelic frequency values for calculation of Combined Paternity Index (CPI) and Probability of Paternity (POP).

Results

No significant variation (p < 0.05) among the allele frequencies at the interpopulation level was observed. The number of obligate alleles and the likelihood of transferring obligate alleles from the putative father showed a positive correlation (p < 0.005) with Power of Discrimination (PD), Polymorphic Information Content (PIC), Power of Exclusion (PE), Paternity Index (PI), Observed and Expected Heterozygosity (Ho and He), and a statistically significant negative correlation (p < 0.005) with Matching Probability (Pm). The average Combined Paternity Index (CPI) and Probability of Paternity (POP) did not show any statistically significant difference (p < 0.05) at the interpopulation level.

Conclusion

The allelic database showed no effect on the CPI and POP in 100 paternity trios. This suggests no urgent need for using population-specific databases for statistical evaluation of paternity trios without inconsistencies.

Keywords:

• Diallelic STRs
• Paternity Index (PI)
• Paternity trios
• allele frequency
• database

Acknowledgements

The authors are highly acknowledged to Director, State Forensic Science Laboratory, Sagar, M. P., India, and Joint Director, Regional Forensic Science Laboratory, Bhopal, M. P., India for providing infrastructure to carry out the research work.

Disclosure statement

No potential conflict of interest was reported by the author(s).