In this collection, the authors present research supporting the claim that the study of autochthonous microbial communities is of crucial importance for understanding the genetic and biotechnological potential of bioremediation in environments close to the areas of extraction and susceptible to contamination. They discuss the main characteristics of petroleum, including its exploitation aspects, the process of geological formation, and environmental impacts. Following this, this book suggests that in case of accidental defects occurring in any part of the system, a coordinated counteraction of numerous mediators may successfully help in the restoration of physiologic processes by means of either overexpression or hyperactivity. Even serious defects of genome stabilizer mechanisms may be kept in balance for a long duration, showing the clinical signs of good health. The authors go on to discuss Rett Syndrome, a rare, neurodevelopmental genetic disorder that develops in early childhood and influences many functions within neurobehavioural domains. The core of phenotype symptoms includes severe linguistic and motor impairments. The correlations between genotype and motor abilities in subjects with Rett Syndrome are discussed. Next, this book examines Cornelia de Lange syndrome (Cd LS) (also known as Bushy syndrome, Amsterdam dwarfism and Brachmann- de Lange syndrome) a genetic multi system disorder, usually caused by spontaneous mutation. The estimated occurence is about 1:10, 000-30, 000 births. A separate paper is presented illustrating the clinical variability of cognitive-behavioral phenotype in the different SCAs, determining that a precise identification of the cognitive and behavioral phenotype in different SCAs may enhance the clinical treatment, anticipatory guidance, and care throughout the lifespan. Transcranial direct current stimulation (t DCS), a non-invasive, painless brain stimulation treatment, is examined. t DCS uses direct electrical currents of low intensity to stimulate specific parts of the brain.