readdepthia

Readdepthia is a term used in genomics and bioinformatics to describe a pattern of abnormal sequencing read depth across genomic regions. It is not a formal clinical diagnosis but a descriptive label applied to datasets in which read depth significantly deviates from the expected baseline in a systematic way. Such patterns can result from true biological variation, such as copy number alterations, or from technical artifacts introduced during library preparation, sequencing, or alignment.

Common contributors include GC-content biases, regions of low mappability, repetitive sequences, batch effects, and insufficient normalization. Readdepthia is typically identified during quality control and CNV analysis when normalization and segmentation fail to produce stable, interpretable results. Practitioners distinguish genuine copy number changes from read depth anomalies by combining depth information with allelic balance, paired-end mapping signals, and external controls.

Impact and handling: In studies relying on depth-based measurements, readdepthia can bias copy number calling, variant detection, and downstream analyses. Mitigation strategies include implementing robust normalization (e.g., GC correction, quantile normalization), using multiple sequencing platforms, applying depth-aware CNV callers, and integrating orthogonal data (such as SNP arrays or RNA expression).

Status: The term readdepthia has appeared in some discussions and methodological reviews as a shorthand for depth-related data quality concerns. It has no formal standing in clinical nomenclature or widely adopted diagnostic criteria.

See also: sequencing depth, read depth, copy number variation, coverage bias, mappability, GC-content correction.