I don't spend a lot of time on genetics but as I remember it:

Compartment A weakening- Active chromosomes being weakened.

A/B mixing - Inactive and active chromosomes coming in contact and potentially affecting each other when they are supposed to be kept in separate compartments to avoid that.

Intra-TAD contact - Genes that exist to help enhance, promote or silence specific other genes can affect genes they were not intended to, thanks to the isolating boundaries being broken.

Decreased H3K27ac modification - (This one I kinda remember) This reduces the likelihood of DNA correctly copying sections when signalled (enhanced) and causes some genes to not be enhanced. This is a problem because sections like our opposable thumbs and brain development have been linked to enhancer genes doing their thing, of which many depend on H3K27AC modification to help.

Hope that helps.