Paternity testing using Y-STR haplotypes: assigning a probability for paternity in cases of mutations

Area of Science:

• Forensic genetics
• Population genetics
• Human genetics

Background:

• Y-chromosomal short tandem repeat (STR) analysis is increasingly vital for parentage testing, especially for male children.
• Multilocus haplotypes can exhibit single-locus differences between related individuals due to mutations.

Observation:

• Investigates the occurrence and impact of single mutation events in Y-chromosomal STR profiles within related males.
• Focuses on the specific challenge of interpreting Y-STR data when mutations are suspected.

Findings:

• Presents a novel likelihood-based methodology for calculating paternity probability.
• This approach explicitly incorporates the possibility of a single mutation event on the Y-chromosome.
• The methodology was successfully applied to two real-world case examples.

Implications:

• Enhances the accuracy and reliability of paternity testing involving male subjects.
• Provides a robust statistical framework for forensic geneticists dealing with Y-STR data.
• Improves the interpretation of genetic evidence in cases of suspected mutation.