Epigenetic signals differ across alleles (2/18/2010)
Researchers from the Institute of Psychiatry (IoP), King's College London, have identified numerous novel regions of the genome where the chemical modifications involved in controlling gene expression are influenced by either genetic variation or the parental origin of that particular stretch of DNA. This contradicts previous assumptions that epigenetic signals are generally equal across both copies of a given region of the genome, except at a small number of known imprinted genes.
Sequencing the genome was only the first step in our quest to understand how genes are expressed and regulated. Epigenetics is the study of alterations to gene function, traditionally believed to occur independently of the DNA sequence. The epigenome sits above the DNA sequence and provides a second layer of information, regulating several genomic functions, including when and where genes are turned on or off. One of the best understood epigenetic mechanisms is DNA methylation, a chemical modification to DNA that can interfere with gene expression.
In the first quantitative genomic survey of allele-specific DNA methylation, published 11 Feburary 2010 in The American Journal of Human Genetics, scientists used sensitive high-throughput technology to detect evidence for skewed gene DNA methylation across both alleles - or copies - of the DNA sequence at almost 1 million positions in the genome.
Lead researcher Dr Jonathan Mill, Medical Research Council Social Genetic, Developmental and Psychiatry Centre at the IoP said: "Interestingly, we found numerous examples where DNA methylation was not equal across alleles - in some instances this depended upon genotype, and in other cases it depended upon which parent that allele was inherited from.
He continues: "Our data show that allele-specific DNA methylation is a widespread phenomenon with potentially over 35,000 such sites occurring across the genome. It appears that a spectrum of skewing is likely, differing between individuals and across tissues.
Dr Mill concludes: "These findings impact upon our understanding about the origin of biological variation and have implications for genetic studies of complex disease including most psychiatric conditions. Because DNA methylation can also be influenced by various environmental factors, the variation we have uncovered provides a potential substrate for interactions between nature and nurture."
Note: This story has been adapted from a news release issued by the King's College London
Post Comments:
| 
Subscribe
Using earthquake sensors to track endangered whales
Grammar errors? The brain detects them even when you are unaware
Principles of locomotion in confined spaces could help robot teams work underground
Using clay to grow bone
European winter weather harder to forecast in certain years
World's smallest droplets
Beautiful 'flowers' self-assemble in a beaker
Do potatoes grow on vines? A review of the wild relatives of some favorite food plants
Ultraresponsive magnetic nanoscavengers for next generation water purification
Same musicians: Brand new tune
Researchers perform fastest measurements ever made of ion channel proteins
Astronomers discover surprising clutch of hydrogen clouds lurking among our galactic neighbors
Western Indian Ocean earthquake and tsunami hazard potential greater than previously thought
New discovery of ancient diet shatters conventional ideas of how agriculture emerged
Untangling the tree of life
World's first handheld sound camera ready for market
More effective, cheaper concrete manufactured with ash from olive residue biomass
Seahorse's armor gives engineers insight into robotics designs
New quantitative analysis for open source software projects
High-volume Bitcoin exchanges less likely to fail, but more likely breached, says study
Computer scientists develop video game that teaches how to program in Java
Do palm trees hold the key to immortality?
Researchers show how we can do math problems unconsciously
Keep moving and have fun
New strategy for fingerprint visualization developed at Hebrew University
Children's bicycle helmets shown to be effective in impact and crush tests
How Usain Bolt can run faster -- effortlessly
Enhancing cognition in older adults also changes personality
Carnivorous plant throws out 'junk' DNA
What is the role of double-stranded RNA in antiviral host defense systems?
Mining the botulinum genome
Sacred lotus genome sequence enlightens scientists