Some people age faster than others, but the discovery of a DNA body clock by UCLA researchers now shows that different parts of our bodies age faster than others. The discovery offers important insights into the aging process — and what we might be able to do about it.
New research, which was conducted by Steve Horvath, a professor of human genetics at the David Geffen School of Medicine at UCLA and of biostatistics at the UCLA Fielding School of Public Health, is the first to show an internal clock able to accurately assess the age of various human organs, tissues, and cell types. And remarkably, certain parts appear to age faster than others.
To create the clock, Horvath studied DNA methylation, a naturally occurring process that chemically alters DNA. And indeed, scientists are increasingly learning that many manifestations of aging are caused by epigenetic factors — those changes to our DNA that happen after we’re born. As an epigenetic process, methylation is a crucial component of normal development and cellular differentiation. It can suppress the expression of viral genes and other biological nonsense that accumulates over time. Regrettably, it also plays a crucial role in aging and the development of nearly all types of cancer.