Dealing with pseudogenes in molecular diagnostics in the next-generation sequencing era

Area of Science:

• Genomics
• Clinical Genetics
• Bioinformatics

Background:

• Pseudogenes, non-functional gene copies, pose challenges in clinical genetic analysis.
• Higher mutation rates in pseudogenes can lead to misinterpretation of sequencing data.
• Accurate gene analysis is critical for diagnosing Mendelian disorders.

Purpose of the Study:

• To address challenges in applying next-generation sequencing (NGS) for analyzing genes with pseudogenes in a clinical setting.
• To highlight the importance of target enrichment and mapping strategies.
• To provide practical insights for reliable genetic analysis.

Main Methods:

• Comparison of PCR-based and capture-based target enrichment methodologies.
• Discussion of critical parameters for mapping strategies to differentiate functional genes from pseudogenes.
• Analysis of genes with known pseudogenes associated with Mendelian disorders using various NGS platforms and library preparations.

Main Results:

• Identified advantages and disadvantages of different target enrichment techniques.
• Outlined key considerations for accurate sequence mapping to distinguish gene families.
• Demonstrated NGS application on diverse platforms for genes with pseudogenes.

Conclusions:

• Effective target enrichment and mapping are essential for accurate clinical interpretation of NGS data involving pseudogenes.
• Careful methodological choices are crucial to avoid pseudogene contamination.
• The presented strategies and examples aid in improving diagnostic yield for genetic disorders.