5/5. I’m deeply grateful to my amazing co-first author Ailsa Jeffries — it was a joy to work together on this project. Special thanks to my mentors Michael Lodato and Zhiping Weng for their guidance and support throughout this work.

4/5. Finally, a linear model showed that high basal expression and short gene length are linked to decreased expression with ageing.
Housekeeping genes are short and highly active. Our analysis suggests they are prone to damage, mutation, and disrupted expression and function during ageing.

3/5. Using scWGS, we identified somatic SNVs in neurons. Signature analysis revealed a predominant age-related mutation signature (A1; mainly C>T and T>C). Signature A1 mutations accumulate at ~12.1 per neuron per year and are likely driven by transcriptional activity.

2/5. We further found that housekeeping genes (involved in ribosomes, transport, and metabolism) show a common decrease in expression across both neurons and glia. Conversely, neuron-specific gene expression generally remains stable throughout life.

1/5. Using snRNA-seq, we found no differences in the overall ratios of neurons to glia or excitatory to inhibitory neurons. However, we identified subtypes of excitatory neurons and astrocytes unique to the infant PFC. These infant-specific cells are enriched for neurodevelopmental genes.

6/6. The two-phased response mirrors the innate and adaptive immunity: first recognize the pattern then the sequence of a new invader. Analyzing 400+ published koala DNA-seq data revealed the second phase response trigger – MAP4K4 KoRV-A provirus – is under selection and sweeping to fixation.