[Microdeletion and Mutation of Y Chromosome in Full Sibling Identification]

Area of Science:

• Forensic Genetics
• Human Genetics
• Molecular Biology

Background:

• Y chromosome microdeletions and mutations can complicate sibling identification.
• Accurate full sibling identification is crucial in forensic and genetic investigations.

Purpose of the Study:

• To explore effective identification methods for full siblings with Y chromosome abnormalities.
• To evaluate the reliability of combined genetic analysis techniques for sibling determination.

Main Methods:

• DNA extraction and analysis of Y-chromosome Short Tandem Repeats (Y-STR) and autosomal STR.
• Calculation of full sibling probability using Identity by State (IBS), Identity by State (ITO), and discriminant functions.
• Assessment of Y chromosome microdeletions and mutations in the samples.

Main Results:

• Detected 2 Y-STR loci mutations and 19 loci deletions in one sample.
• Achieved an IBS score of 53 (above the threshold of 42) and a Full Sibling Index (FSI) of 1.36×10¹⁶.
• Discriminant function analysis indicated a higher probability of the individuals being full siblings.

Conclusions:

• The integrated application of IBS, ITO, and discriminant functions provides a robust approach for full sibling identification.
• These methods are reliable for expert opinion in cases involving Y chromosome microdeletions and mutations.
• The study validates a comprehensive strategy for complex Y chromosome genetic analyses.