BackgroundMitochondrial heteroplasmy, the presence of more than one mitochondrial DNA (mtDNA) variant in a cell or individual, is not as uncommon as previously thought. It is mostly due to the high mutation rate of the mtDNA and limited repair mechanisms present in the mitochondrion. Motivated by mitochondrial diseases, much focus has been placed into studying this phenomenon in human samples and in medical contexts. To place these results in an evolutionary context and to explore general principles of heteroplasmy, we describe an integrated cross-species evaluation of heteroplasmy in mammals that exploits previously reported NGS data. Focusing on ChIP-seq experiments, we developed a novel approach to detect heteroplasmy from the concomitant mitochondrial DNA fraction sequenced in these experiments.ResultsWe first demonstrate that the sequencing coverage of mtDNA in ChIP-seq experiments is sufficient for heteroplasmy detection. We then describe a novel detection method for accurate detection of heteroplasmies, which also accounts for the error rate of NGS technology. Applying this method to 79 individuals from 16 species resulted in 107 heteroplasmic positions present in a total of 45 individuals. Further analysis revealed that the majority of detected heteroplasmies occur in intergenic regions.ConclusionIn addition to documenting the prevalence of mtDNA in ChIP-seq data, the results of our mitochondrial heteroplasmy detection method suggest that mitochondrial heteroplasmies identified across vertebrates share similar characteristics as found for human heteroplasmies. Although largely consistent with previous studies in individual vertebrates, our integrated cross-species analysis provides valuable insights into the evolutionary dynamics of mitochondrial heteroplasmy.Electronic supplementary materialThe online version of this article (doi:10.1186/s13059-016-0996-y) contains supplementary material, which is available to authorized users.

Abstract-We present an implementation of our deadlock immunity system, Dimmunix, for mobile phone software. Within Android 2.2 OS, we modified Dalvik VM, the JVM running all the Android applications, to provide platform-wide deadlock immunity. We successfully ran the Dimmunix-enabled Android 2.2 OS on a Nexus One phone. On the phone, we reproduced a real deadlock involving Android's NotificationManagerService and StatusBarService classes, which froze the entire phone's interface. Android Dimmunix successfully detected the deadlock, and subsequently prevented its reoccurrence, with no user intervention. Our tests show that Android Dimmunix incurs 4-5% performance overhead and 4% memory overhead. Therefore, Android Dimmunix is a practical and efficient solution to cope with deadlocks on mobile phones. To the best of our knowledge, Android Dimmunix is the first failure immunity system for mobile phones, and the first one to provide platformwide failure immunity.