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Published on: October 20, 2019
[Empirical Classification of Tri-Allelic Genotype Cases and Parentage Index Calculation]
Objectives:
To standardize the calculation method of the parentage index (PI) for short tandem repeat (STR) tri-allelic genotypes, thereby ensuring the accuracy and reliability of parentage tes‑ ting conclusions.
Methods:
A systematic analysis of 160 real cases was conducted. A classification system was constructed based on the occurrence mechanisms and inheritance patterns of STR tri-alleles, and the PI calculation method was optimized by integrating previous research findings with empirical data.
Results:
A mechanism-based classification system for STR tri-allelic genotypes was established, comprising Type I (2 subtypes), Type II (6 subtypes), and the trisomic type (2 subtypes). On this basis, a standardized PI calculation method covering all categories of STR tri-allelic genotypes was developed.
Conclusions:
This study provides methodological guidance for the scientific and standardized calculation of PI for STR tri-allelic genotypes and offers an important reference for the formulation and refinement of relevant industry standards.
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