Mouse Genetics and Gene Targeting provides a number of services. Descriptions are detailed below.
All service rates are indicated at the point of initiating service requests within the iLab.
Microinjection of purified DNA constructs for the production of transgenic mice. This includes injection of a single transgene construct (plasmid-based or BACs) that has been prepared by the investigator. A minimum of 2 transgenics or 20 live births (or embryos), whichever comes first, is prepared for each set of injections charged to an investigator. Standard transgenic founders are established in either B6D2 hybrids or FVB/N inbreds, while injections can be done in less efficient strains (such as C57Bl/6J) as well. (The cost of mice and health testing are an additional cost and will be added at the time of billing.)
Protocols for the purification of plasmid-based transgenes that are less than 20 kb, and for the purification of tail DNAs for genotyping of potential founders as follows:
Recent advances in the field have allowed the MGGT CoRE to use CRISPR technology to do genome editing in vivo. This approach allows the CoRE to create novel targeted genes (knock-outs, knock-ins, etc.) in as little as 1-2 months, compared with the generation of similar targeted models using ES cells which can take 6-12 months, or more. (The cost of mice and health testing are an additional cost and will be added at the time of billing.)
Mouse lines can be imported into Mount Sinai by obtaining 1-2 males from a collaborator at another institution. These males are used to prepare sperm for in vitro fertilization (IVF) of wild-type mouse oocytes. The fertilized embryos are transferred to specific pathogen-free hosts to generate clean mice.
(The cost of mice and health testing are an additional cost and will be added at the time of billing.)
IVF and frozen embryo recovery
The MGGT CoRE recovers lines from which sperm have been frozen and stored at Mount Sinai. Cryopreserved sperm samples are maintained in two separate locations to minimize losses in the case of a freezer failure. The MGGT CoRE also works with investigators to import lines of mice into Mount Sinai through the use of live, early-stage embryos, frozen embryos or frozen sperm. These methods can offer a relatively quick solution to importation of animals that avoids quarantine issues such quarantine space, and the quarantine time itself. (The cost of mice and health testing are an additional cost and will be added at the time of billing.)
ES cell injection
Microinjection of selected embryonic stem (ES) cell clones into mouse blastocysts to establish chimeric mice for the production of "knockout" mouse lines. Depending upon the goals of the study, live offspring, or pre-implantation or mid-gestation embryos can be provided. (The cost of mice and health testing are an additional cost and will be added at the time of billing.)
ES Cell Karyotyping
The quality of ES cells can be assessed prior to injection to create chimeric mice by karyotyping individual ES clones. This should be considered whenever possible, especially in cases where multiple clones are available, so that the best clones can be chosen for microinjection into blastocysts.
The long-term storage of mouse sperm and/or embryos reduces the need for constant maintenance of lines which are not essential for current research needs, as well as providing a backup repository of important lines in case of environmental or weather-related crises. (The cost of mice for the CryoPlus service is an additional cost and will be added at the time of billing.)
Mouse lines infected with various mouse pathogens can be cleaned up by transfer of embryos to pathogen-free hosts. This will allow these lines to be shipped to collaborators at other institutions or to be moved into cleaner, barrier facilities at Mount Sinai. (The cost of mice and health testing are an additional cost and will be added at the time of billing.)
Shipment of Cryopreserved Sperm
Cryopreserved sperm samples can be shipped from Mount Sinai to collaborators around the world. This service includes preparation and loading of dry liquid nitrogen shippers with frozen sperm samples.
The MGGT CoRE can provide mouse embryos at various preimplantation stages. (The cost of mice is an additional cost and will be added at the time of billing.)
ES cell generation from existing lines
The MGGT CoRE can produce ES cells from blastocysts of existing mouse lines. This is a useful technique for laboratories that would like to generate their own ES cells for in vitro or in vivo studies.
ES Cell Subcloning
The CoRE can use sub-cloning techniques to produce high quality ES cells from lines which have lost their germline potential. This approach will be useful in cases where ES cells fail to produce germline transmission due to changes in karyotype, etc.
Services and Timeline FAQs
Below we answer some of the most frequently asked questions about our services.