Alterations in DNA replication timing identify TP63 as a novel marker of progeroid diseases [Chip]

Progeroid syndromes are rare genetic disorders that phenotypically resemble natural aging. Despite identification of causal mutations, mechanisms that generate their clinical manifestations remain elusive. Here, we identified a DNA replication timing (RT) signature that distinguishes progeroid syndromes from normal aging and identifies TP63 gene as a new disease marker. Abnormal TP63 RT appears early during differentiation of progeroid iPSCs and is associated with altered gene variant expression. Our findings demonstrate the utility of RT signatures to identify novel biomarkers not detected by other methods, reveal abnormal TP63 RT as an early event in progeroid disease progression and offer TP63 gene regulation as a potential therapeutic target. Genome-wide replication timing profiles were constructed from HGPS patients, normal individuals of different ages and cells entering cellular senescence.