*The Mouse Gene Manipulation Core is now open. Please review our new COVID-19 standard operating procedures before booking or arriving to the core.
The mission of the Gene Manipulation Core is to provide Boston Children's Hospital investigators with easily accessible, efficient, cost effective and quality controlled genetically altered mouse models, utilizing the latest genome editing techniques.
Transgenic and gene targeted models have been utilized for several decades to generate mouse models and while we continue to offer this service, CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Regions/ CRISPR associated protein) technology represents a much more powerful and precise tool to create gene edited mice and this has become the service of choice for gene editing in the core.
CRISPR/Cas9 utilizes target specific guide RNA, Cas9 protein and/or donor template introduced by microinjection into one-cell embryos. CRISPR/Cas9 mediated genome editing relies on the combined effect of target sequence specific guide RNA and Cas9 nuclease induced double strand break (DSB). Cellular repair mechanisms repair DSB by two pathways: 1) non-homologous end joining (NHEJ), and 2) homology directed repair (HDR). NHEJ is an error prone highly efficient mechanism that actively repairs DSB and in this process introduces insertion or deletion (InDel) of nucleotides, often resulting in premature stop codon, leading to loss of gene function thus creating a gene knockout (KO). HDR is a less efficient but more precise repair mechanism and is used to introduce accurate modification by supplying a donor template in the form of single or double strand DNA with specific changes flanked by homology arms.
The Gene Manipulation core has since late 2015 begun to utilize this single step founder generation technique to produce gene knockout and knock-in, conditional allele, insertion of reporter genes, Cre drivers and KO of multiple loci. Almost all gene targeting performed by the core is now CRISPR/Cas9 based.
The core also serves as an in-house repository of cryopreserved mouse strains in the form of embryos and/or sperm to archive valuable mouse strains. The cryopreservation service saves space and cost of live colonies and prevents accidental loss of invaluable strains.
The core also provides resources and comprehensive knowledge of complex mouse model generation; genotyping founder lines, breeding strategies etc. The core remains vigilant in evaluating new gene manipulation technologies, their effectiveness and demand, cost and limitations. Cost effectiveness of service fee is established by an annual review of service fees offered by other Longwood/Harvard core facilities and fees are adjusted accordingly. Furthermore, we respond to users' feedback regarding the types of support and services they require. The technology required for CRISPR/Cas9 genome editing, culturing and genetic modification of ES cells, micromanipulation of pre-implantation mouse embryos and embryo transfer by mouse survival surgeries, are best fulfilled by a core facility. These procedures require quality-controlled reagents, microinjection and mouse surgery require specialized skills, equipment, and dedicated mouse colonies. The costs of developing and maintaining the ability to perform these procedures are prohibitive to most investigators, especially those that generate new mouse lines infrequently.
Consolidation of these technologies within a core facility serving multiple investigators allows individual investigators access to specialized techniques that might otherwise not be available to them except by very expensive commercial vendors.
Mouse core routinely perform in vivo genome editing service using CRISPR/Cas9 technology and generated more than 200 novel mouse models.
We are funded by NIH P50 HD105351.
Mantu Bhaumik, PhD
Assistant Director
617-919-2128
Center for Life Sciences
3 Blackfan Circle
CLS 12122-12124
Boston, MA 02215
9 a.m to 5 p.m.