Background and objectives of the study Scientists at the Institute for Farm Animal Genetics at the Friedrich Loeffler Institute, Germany have used the CRISPR/Cas9 to genome edit pigs so that they develop female reproductive organs even though they have a male set of chromosomes. The authors state that their results can be used to avoid […]
Background – epigenetics The field of epigenetics deals with hereditary changes that do not change the DNA sequence itself. Epigenetic markers determine which genes are activated or silenced in certains cells and tissues, so they influence gene expression. Thus, the basic structure of the DNA remains unchanged. Epigenetic markers are biochemical appendages of DNA. Epigenetics […]
CRISPR/Cas9 was supposed to be used in this study to change a mutation in human embryos that cause a genetic disease. This disease is mediated by a mutation in the EYS gene and causes blindness (retinitis pigmentosa, retinal degeneration). The scientists envisaged that CRISPR/Cas9 causes a double-strand break (DSB) within the mutated EYS gene of […]
Double-strand breaks (DSBs) in DNA occur naturally in every organism (microoorganisms, plants, animals, humans) and are mended by the cell’s own repair mechanisms. The original state before the DNA damage can be restored or the genome can be changed at that particular region, i.e. the introduction of small insertions, deletions or point mutations. In addition […]
In this study, the CRISPR/Cas3 system from Pseudomonas aeruginosa type I-C is presented as a new tool for genome editing applicable in various bacteria. Compared to the “classic” Cas9 gene scissors from Streptococcus pyogenes, Cas3 has two distinct functions: on the one hand, Cas3 cuts a single strand of DNA in its function as a […]
In this PrePrint study, a containment strategy is presented to ensure that genetically modified (GM) bacteria cannot survive outside the laboratory. The bacteria are equipped with a dependency on a certain synthetic compound. The GM bacteria can only grow if this particular substance is added to the culture medium. If the compound is not available, […]
In this study, genetic elements with which gene drives in the genome of fruit flies can either be switched off or completely removed are presented. These mechanisms are based on the transmission of specific guide RNAs (gRNAs, signposts for the CRISPR/Cas9 gene scissors), which determine the target region(s) in the genome and are intended here […]
Before the gene scissors CRISPR/Cas is able to recognize and change target areas of the genome of plants, it must first be introduced into their cells. Scientists have various methods of old genetic engineering to choose from: a ring-shaped piece of DNA (a so called plasmid) containing foreign DNA can be introduced into the cells […]
The aim of the study is to introduce polledness (hornlessness) into dairy cows with the help of the CRISPR/Cas gene scissors. Polledness occurs naturally in cattle breeds such as Angus, which are used in beef cattle breeding, but much less often in dairy cows. In the study, the scientists used CRISPR/Cas12a, a variant of the […]
This study deals with unintended on-target changes in the genome of human cell lines after a DNA double-strand break (DSB) was generated at the target region using the gene scissors CRISPR/Cas. It is important to consider the structure and function of chromosomes to properly understand the effects found here: Humans have two complete sets of […]
