The prevalence of Autism Spectrum Disorder (ASD) has increased by roughly 30% since 2012. The CDC recently reported that one in 68 children in the United States is affected by ASD, compared to one in 88 just two years ago. This enhanced occurrence could be attributed to advancements in the detection and diagnosis, increased awareness, or simply that the number of ASD patients is on the rise. Regardless, it is a major problem affecting our nation’s youth. ASD is classified as a neurodevelopmental disorder that impacts behavior, social interactions, and communication skills and can range from mild to severe depending on the individual. There are many factors believed to influence ASD including; environmental, genetic and recently discovered epigenetic regulations. Earlier this year, Zhubi et al. published a paper regarding the importance of 5- hydroxymethylcytosine (5-hmc) in mediating the complex interaction between methyl CpG binding protein-2 (MeCP2) and two genes, glutamic acid decraboxylase (GAD1) and Reelin (RELN), each of which has been shown to be decreased in the brain of ASD patients.
April is Autism Awareness Month: Increased levels of 5-hmC may influence gene regulation in Autism Spectrum Disorder
Breast cancer is one of the most common cancers worldwide in females. Researchers from the University of California, Los Angeles (UCLA) found that PIAS1 is linked to breast tumorigenesis. PIAS1 is a transcriptional repressor that has SUMO (small ubiquitin-like modifier) E3 ligase activity. Recently, it had been explored that PIAS1 facilitates a novel epigenetic mechanism to control T cell differentiation. In Liu et al., researchers from the City of Angels reported that PIAS1 SUMO ligase was involved in the progression of breast tumorigenesis. Their studies identified a novel epigenetic mechanism that regulates tumorigenesis through selective gene silencing.
While DNA methylation is probably the longest studied and best understood epigenetic modification, methylation of RNA is gaining increased appreciation, especially recently. N6-methyladenosine (m6A) in RNA has been observed to be the most frequently occurring epigenetic modification in mRNAs in eukaryotic organisms, but the function of this modification is still poorly understood. A recent paper by Wang et al. reports that the m6A modification in RNA acts to destabilize transcripts and that RNA methylation is important for keeping embryonic stem cells in their undifferentiated and pluripotent state. Furthermore, the authors hypothesize that RNA methylation is a critical activity in cell biology and might also play a central role in numerous RNA-mediated cellular processes.
Cigarette smoking leads to some of the most preventable causes of death and illness in the world. The Centers for Disease Control (CDC) in the United States has reported that there are approximately 440,000 deaths due to smoking each year, and an additional 49,000 deaths due to secondhand smoke. Roughly 600 chemicals are found in a cigarette, and after burning approximately 4,000 chemicals are generated, so it is not surprising that smoking can lead to various diseases, such as emphysema, cancer, and heart-related diseases. Past studies have shown correlations between smoking and changes in DNA methylation levels at certain genes, but the effect of smoking on DNA methylation is different between ethnic groups due to genetic and behavioral differences between populations. Learning more about the susceptibility of different ethnic groups to smoking-related diseases is of great importance due to the recent increases in tobacco use in certain parts of the world, such as South Asian countries, because the increased smoking rates will lead to future population health issues.
Many scientists are hopeful that studying aberrant epigenetic patterns will help us find promising biomarkers for early diagnosis and prognosis of carcinogenesis. Among such markers, there has recently been heightened interest in 5-hydroxymethylcytosine (5-hmC), which is an enzymatically-modified form of 5-methylcytosine (5-mC). A group of researchers in Europe investigated changes in 5-mC as well as 5-hmC patterns in control and phenobarbital (PB)-treated mice in search for potential biomarkers for the early progression of liver tumorigenesis. Phenobarbital has historically been used to treat convulsions and seizures, but is also known to be a carcinogen in some model systems, such as the mouse model for liver cancer used by the researchers in this report.