Rapidly mutating Y-STRs study in Chinese Yi population.

Area of Science:

• Genetics
• Forensic Science

Background:

• Conventional Y-chromosomal short tandem repeats (Y-STRs) have limitations in differentiating closely related males due to low mutation rates.
• Rapidly mutating Y-chromosomal short tandem repeats (RM Y-STRs) exhibit higher mutation rates, enhancing their discriminatory power.

Purpose of the Study:

• To evaluate the efficacy of 13 RM Y-STR markers in differentiating paternal lineages within the Chinese Yi population.
• To determine the mutation rates and patterns of RM Y-STRs in father-son pairs.

Main Methods:

• Analysis of 260 father-son pairs from the Chinese Yi population using 13 RM Y-STR markers.
• Statistical analysis of observed mutations, including repeat gains/losses and step mutations.
• Calculation of locus-specific and average mutation rates.

Main Results:

• 18.8% of father-son pairs were differentiated using the 13 RM Y-STR markers, closely matching theoretical estimates.
• Repeat gains were more frequent than losses (1.48:1), and one-step mutations predominated (27.5:1).
• The average mutation rate was 1.46 × 10⁻², with an overall combined mutation rate of 1.70 × 10⁻² from previous studies.

Conclusions:

• RM Y-STRs demonstrate high differentiation capacity for distinguishing paternal lineages in the Chinese Yi population.
• The findings support the application of RM Y-STRs in forensic investigations and population genetics for enhanced discrimination.