Skin & Blood DNA Methylation Clock for Ex Vivo Age Estimation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing DNA methylation-based biomarkers for human cells, particularly fibroblasts, are inaccurate and incompatible with ex vivo studies, limiting the ability to effectively measure and track epigenetic aging in cells commonly used in research.

Innovation Solution

A novel DNA methylation biomarker, the 'skin & blood clock', which accurately measures the age of human fibroblasts, keratinocytes, endothelial cells, and other cell types by analyzing methylation status in 391 specific CpG loci, providing a more precise estimation of epigenetic age.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If existing DNA methylation-based biomarkers are used to estimate epigenetic age in human cells, then age estimation can be performed, but the accuracy is insufficient particularly for fibroblasts and ex vivo studies

Engineering Contradiction:
Improveepigenetic age estimation accuracyVSAvoidbiomarker compatibility with ex vivo studies
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent segments the genome into specific regions containing 391 CpG loci that are most informative for age estimation in fibroblasts and ex vivo models. By focusing on these segmented genomic regions rather than whole-genome analysis, the biomarker achieves higher accuracy for specific cell types while maintaining reliability across different study conditions.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies local quality by developing tissue-specific methylation markers tailored to fibroblasts and ex vivo systems. The 391 CpG loci were selected based on their specific methylation patterns in these cell types, creating a localized solution that optimizes measurement precision for the target application rather than using a universal marker set.

Inventive Principle:
Principle #3Local quality

2Adaptability or versatility

If pan-tissue DNA methylation biomarkers are used, then broad applicability across different tissues is achieved, but accuracy for specific cell types like fibroblasts deteriorates

Engineering Contradiction:
Improvebiomarker applicability across tissuesVSAvoidage estimation accuracy in fibroblasts
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent implements dynamics by creating a flexible biomarker system that can be adapted to different ex vivo models and fibroblast sources. The 391 CpG locus framework provides a dynamic platform that maintains core accuracy for fibroblasts while allowing customization for specific research contexts, balancing specialization with adaptability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies parameter changes by adjusting the methylation threshold values and weighting parameters for the 391 CpG loci based on fibroblast-specific data. This optimization of parameters improves measurement precision for fibroblasts while preserving the biomarker's versatility across different ex vivo study conditions.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The 'skin & blood clock' significantly enhances the accuracy of epigenetic age estimation in human cells, enabling effective evaluation of anti-aging interventions and forensic applications, and predicting lifespan and health outcomes based on DNA methylation patterns.

Implementation Method 1

DNA methylation (DNAm). Chronological time has been shown to elicit predictable hypo- and hyper-methylation changes at many regions across the genome

Methodology Applied
Scientific EffectDNA methylation:

Data Source

PatentEP3802856B1DNA methylation biomarker of aging for human ex VIVO and in VIVO studies
Publication Date: 2025.08.20 RGT UNIV OF CALIFORNIA
  • EP3802856B1 patent drawingFigure 1A~1J
  • EP3802856B1 patent drawingFigure 2A~2I
  • EP3802856B1 patent drawingFigure 3

AI summary

DNA methylation (DNAm) based biomarkers of aging have been developed for many tissues and organs. However, these biomarkers have sub-optimal accuracy in skin cells, fibroblasts and other cell types that are often used in ex vivo studies. To address this challenge, we analyzed DNA methylation array data sets derived from multiple sources of DNA, from which we developed a novel and highly robust DNAm age estimator (based on 391 CpGs) for human fibroblasts, keratinocytes, buccal cells, endothelial cells, lymphoblastoid cells, skin, blood, and saliva samples. The application of this new age estimator to ex vivo cell culture systems revealed that cellular population doubling is generally accompanied by an increase in epigenetic aging. The new skin & blood clock disclosed herein is useful for ex vivo and in vivo studies of human aging.