Genome editing: A breakthrough in life science and medicine [Review]

CRISPR-Cas9 genome editing technology is an emerging tool in life science, clinical and plant research. The technique offers a remarkable specificity and efficiency in gene editing. In this study, we...

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Gene Editing and Genome Engineering with CRISPR-Cas9

Molecular Frontiers Journal ◽

10.1142/s2529732517400119 ◽

2017 ◽

Vol 01 (02) ◽

pp. 99-107 ◽

Cited By ~ 1

Author(s):

Emmanuelle Charpentier

Keyword(s):

Gene Expression ◽

Genome Editing ◽

Gene Editing ◽

Genome Engineering ◽

Life Science ◽

Science Research ◽

Cell Types ◽

Life Science Research ◽

Domains Of Life ◽

Modulation Of Gene Expression

The RNA-programmable CRISPR-Cas9 technology allows precise and efficient engineering or correction of mutations, modulation of gene expression and marking of DNA in a wide variety of cell types and organisms in the three domains of life. Because of its versatility and ease of design, this powerful technology has been rapidly and universally adopted for genome editing applications in life science research. It is also recognized for its promising and potentially transformative applications in biotechnology, medicine and agriculture.

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Prediction of off-target effects of the CRISPR/Cas9 system for design of sgRNA

E3S Web of Conferences ◽

10.1051/e3sconf/202018504018 ◽

2020 ◽

Vol 185 ◽

pp. 04018

Author(s):

Calvin Guo ◽

David Zhen

Keyword(s):

Genome Editing ◽

Life Science ◽

Genetic Diseases ◽

Science Research ◽

New Drugs ◽

Limiting Factor ◽

Widespread Application ◽

Genetic Characteristics ◽

Target Sites ◽

Target Effect

CRISPR/Cas9 genome editing technology is the frontier of life science research. They have been used to cure human genetic diseases, achieve cell personalized treatment, develop new drugs, and improve the genetic characteristics of crops and other fields. This system relies on the enzyme Cas9 cutting target DNA (on target) under the guidance of sgRNA, but it can also cut non-target sites, which results in offtarget effects, thus causing uncontrollable mutations. The risk of off-target effect in CRISPR technology is the main limiting factor that affects the widespread application of CRISPR technology. How to evaluate and reduce the off-target effect is the urgent problem to be solved. In this work, we build up a model that can predict the score of being off-target. Through comparison with the complete genome of the target and precise mathematics that calculate the potential risk of being off-target, we optimize the sgRNA, which is capable of reducing the off-target effect. The result has proven that we can efficiently and quickly identify and screen the best editing target sites with our model. The CRISPR/Cas9 system, not even being perfected yet, has already demonstrated its potential in the field of genome editing. Hopefully through our model, the CRISPR/Cas9 system can quickly apply to more branches in life science and cure those diseases that have been previously incurable.

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The CM120 Biotwin: a high-contrast objective lens, optimum cryo-vacuum and improved EDX performance

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139299 ◽

1995 ◽

Vol 53 ◽

pp. 584-585

Author(s):

Uwe Lücken ◽

Michael Felsmann ◽

Wim M. Busing ◽

Frank de Jong

Keyword(s):

Life Science ◽

Focal Length ◽

Objective Lens ◽

High Contrast ◽

Contrast Imaging ◽

X Ray ◽

Forming Mechanism ◽

Similar Image ◽

High Contrast Imaging ◽

Low Concentrations

A new microscope for the study of life science specimen has been developed. Special attention has been given to the problems of unstained samples, cryo-specimens and x-ray analysis at low concentrations.A new objective lens with a Cs of 6.2 mm and a focal length of 5.9 mm for high-contrast imaging has been developed. The contrast of a TWIN lens (f = 2.8 mm, Cs = 2 mm) and the BioTWTN are compared at the level of mean and SD of slow scan CCD images. Figure 1a shows 500 +/- 150 and Fig. 1b only 500 +/- 40 counts/pixel. The contrast-forming mechanism for amplitude contrast is dependent on the wavelength, the objective aperture and the focal length. For similar image conditions (same voltage, same objective aperture) the BioTWIN shows more than double the contrast of the TWIN lens. For phasecontrast specimens (like thin frozen-hydrated films) the contrast at Scherzer focus is approximately proportional to the √ Cs.

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X-ray mapping without STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017027x ◽

1994 ◽

Vol 52 ◽

pp. 508-509

Author(s):

Judith M. Brock ◽

Max T. Otten

Keyword(s):

Life Science ◽

Materials Science ◽

Chemical Elements ◽

Full Description ◽

Scanning System ◽

Elemental Distribution ◽

X Ray ◽

Transmission Electron ◽

Distribution Of Elements ◽

Made In

A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

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