nCV

nCV quantifies the robustness of circadian clock gene oscillations in population-scale gene expression datasets where sample collection times are unlabeled.

Key Features:

• Normalized coefficient of variation (nCV): Calculates the normalized coefficient of variation for clock gene expression as a metric of oscillation robustness, serving as an alternative to relative amplitude (rAMP).
• Time-independent analysis: Assesses robustness without requiring labeled time points, enabling analysis of datasets lacking sampling time information.
• Correlation with rAMP: Exhibits a linear correlation between nCV and rAMP, providing consistency with established relative amplitude measures.
• Application in cancer research: Detects significantly dampened clock gene oscillations in tumor tissues compared with non-tumor tissues.
• Population-level analysis: Enables evaluation of clock gene robustness across large, population-scale datasets.

Scientific Applications:

• Circadian Biology: Quantifying robustness and stability of circadian rhythms in gene expression datasets without time labels.
• Oncology: Comparing clock gene oscillation robustness between tumor and non-tumor tissues to identify dysregulation associated with cancer.
• Population Health Studies: Assessing circadian rhythm robustness across diverse human populations in large-scale expression studies.

Methodology:

Compute the normalized coefficient of variation for clock gene expression data and compare nCV values to relative amplitude (rAMP) via linear correlation to assess oscillation robustness without time-stamped samples.