A new study increases and strengthens the links that have led scientists to propose the “transposon theory of aging.” Transposons are rogue elements of DNA that break free in aging cells and rewrite themselves elsewhere in the genome, potentially creating lifespan-shortening chaos in the genetic makeups of tissues.
As cells get older, prior studies have shown, tightly wound heterochromatin wrapping that typically imprisons transposons becomes looser, allowing them to slip out of their positions in chromosomes and move to new ones, disrupting normal cell function. Meanwhile, scientists have shown that potentially related interventions, such as restricting calories or manipulating certain genes, can demonstrably lengthen lifespans in laboratory animals.