Researchers grasp wider role for genetic variation in regulatory elements of genome
Complex traits such as height and susceptibility to common diseases like diabetes and heart disease usually stem from a complicated mix of genetics and lifestyle. While changes in many genes themselves play a role, small variations in DNA sequences near genes that control when and how much a gene is turned on and off, or expressed, are often extremely important for gene activity.
To paint a clearer picture of how such variation affects gene activity, Fernando Pardo Manuel de Villena, Ph.D., at the University of North Carolina, Chapel Hill, and his colleagues crossbred several strains of mice and examined regulatory DNA and gene activity in brain and other tissue. They found that more than 80 percent of the mouse genes had variations in the nearby regulatory DNA that affects gene activity.
Genes are inherited in pairs, or alleles, with one allele from each parent. When the researchers compared gene activity due to the genetic contributions from either parent, they found that expression in 95 genes in the brain depended more on being inherited from one parent than the other - a process called imprinting. They also unexpectedly discovered that for thousands of genes in the brain, there was a slightly greater expression of genes inherited from the father than from the mother.
The findings, reported online March 2, 2015 in the journal Nature Genetics, provide new insights into the effects and roles of genetic variation and parental influence on gene activity in mice and humans, as well as the cause of complex traits and disease in both species. The research was supported by the Centers for Excellence in Genome Sciences program from the National Human Genome Research Institute (NHGRI) and the National Institute of Mental Health (NIMH), and with funding from the National Institute of General Medical Sciences (NIGMS). NHGRI, NIMH, and NIGMS are parts of NIH.
Crowley, et al. Analyses of allele-specific gene expression in highly divergent mouse crosses identifies pervasive allelic balance. Nature Genetics. March 2, 2015, DOI: 10.1038/ng.3222. [PubMed]
Jeffrey Struewing, M.D., program director, Division of Genomic Medicine, NHGRI; Andrea Beckel-Mitchener, Ph.D., chief, Functional Neurogenomics Program, Division of Neuroscience and Basic Behavioral Science, NIMH
NHGRI is one of the 27 institutes and centers at the National Institutes of Health. The NHGRI Extramural Research Program supports grants for research and training and career development at sites nationwide. Additional information about NHGRI can be found at http://www.genome.gov.
About the National Institute of Mental Health (NIMH): The mission of the NIMH is to transform the understanding and treatment of mental illnesses through basic and clinical research, paving the way for prevention, recovery and cure. For more information, visit the NIMH website.
NIGMS supports basic research to increase our understanding of biological processes and lay the foundation for advances in disease diagnosis, treatment and prevention. For more information on the Institute's research and training programs, see http://www.nigms.nih.gov.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 institutes and centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.