Genomic imprinting in humans


Columbia University College Of Physicians and Surgeons


Benjamin Tycko, MD, PhD, professor of pathology in the Institute for Cancer Genetics and the Taub Institute, Columbia University College of Physicians & Surgeons


In most cases, people inherit two working copies of a gene—one from each parent. In genomic imprinting, the addition of an epigenetic tag (e.g., a methyl group) during egg or sperm development silences one of the alleles, from either the mother or the father. This phenomenon had previously been observed in mice. Previously, researchers had found that only the maternal allele of H19 was active, the paternal allele having been silenced. Subsequently, Tycko and colleagues discovered that maternal imprinting of H19 also occurs in humans. This finding has implications for cancer treatment, in which paternally or maternally imprinted oncogenes may be modified in a single step.