Extensive variation in chromatin states across humans

Area of Science:

• Genomics
• Epigenetics
• Human population genetics

Background:

• Most disease-associated genetic variants are non-coding, implicating regulatory regions in disease susceptibility.
• Understanding variation in gene regulatory elements is crucial for deciphering disease predisposition.

Purpose of the Study:

• To investigate variations in chromatin states across diverse human populations.
• To explore the relationship between chromatin variability, genetic variation, and gene regulation.

Main Methods:

• Analysis of five histone modifications, cohesin, and CTCF in lymphoblastoid cell lines from 19 individuals.
• Comparison of chromatin states and enhancer activity across individuals.
• Assessment of genetic inheritance and correlation with population divergence.

Main Results:

• Extensive variation in regulatory region chromatin states observed, with frequent switching between active and repressed states.
• Enhancer activity displayed significant inter-individual diversity, while gene expression remained relatively stable.
• Chromatin variability demonstrated genetic inheritance, correlated with genetic variation, and linked to transcription factor binding motif disruptions.

Conclusions:

• Human chromatin states in regulatory regions are highly variable and influenced by genetics.
• This variability contributes to understanding human genetic diversity and disease association.
• Findings provide insights into the dynamic nature of the human epigenome.