Steve Horvath

Steve Horvath is a German–American aging researcher, geneticist, and biostatistician. He is a professor at the University of California, Los Angeles. He is known for developing the Horvath aging clock, which is a highly accurate molecular biomarker of aging, and for developing weighted correlation network analysis. His work on the genomic biomarkers of aging, the aging process, and many age related diseases/conditions has earned him several research awards. Horvath is a principal investigator at the anti-aging startup Altos Labs and co-founder of nonprofit Clock Foundation.

Horvath was born 1967 in Frankfurt, Germany; as the family name Horvath indicates, he is of Hungarian ancestry. He received his Diplom in Mathematics and Physics at Technische Universität Berlin, graduating in 1989. He received his Ph.D. in mathematics at the UNC Chapel Hill in 1995 and his Sc.D. in biostatistics at Harvard in 2000. In 2000, Horvath joined the faculty of the University of California, Los Angeles, where he is 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.

Horvath's development of the DNA methylation based age estimation method known as epigenetic clock was featured in Nature magazine. In 2011, Horvath co-authored the first article that described an age estimation method based on DNA methylation levels from saliva. In 2013 Horvath published a single author article on a multi-tissue age estimation method that applies to all nucleated cells, tissues, and organs. This discovery, known as the Horvath clock, was unexpected because cell types differ in terms of their DNA methylation patterns and age related DNA methylation changes tend to be tissue specific. In his article, he demonstrated that estimated age, also referred to as DNA methylation age, has the following properties: it is close to zero for embryonic and induced pluripotent stem cells, it correlates with cell passage number; it gives rise to a highly heritable measure of age acceleration; and it is applicable to chimpanzees. Since the Horvath clock allows one to contrast the ages of different tissues from the same individuals, it can be used to identify tissues that show evidence of increased or decreased age.

Horvath co-authored the first articles demonstrating that DNA methylation age predicts life-expectancy and is positively associated with obesity, HIV infection, Alzheimer's disease, cognitive decline, Parkinson's disease, Huntington's disease, early menopause, and Werner syndrome.

Horvath published the first article demonstrating that trisomy 21 (Down syndrome) is associated with strong epigenetic age acceleration effects in both blood and brain tissue. Using genome-wide association studies, Horvath's team identified the first genetic markers (SNPs) that exhibit genome-wide significant associations with epigenetic aging rates – in particular, the first genome-wide significant genetic loci associated with epigenetic aging rates in blood notably the telomerase reverse transcriptase gene (TERT) locus.

As part of this work, his team uncovered a paradoxical relationship: genetic variants associated with longer leukocyte telomere length in the TERT gene paradoxically confer higher epigenetic age acceleration in blood.

Horvath proposed that slower epigenetic aging rates could explain the mortality advantage of women and the Hispanic mortality paradox.

Horvath published the first large scale study of the effect of lifestyle factors on epigenetic aging rates.