Services & Prices

Electroporating 1-cell mouse embryos with CRISPR reagents is generally a more efficient way to introduce a mutation. It usually requires fewer embryos to achieve your goal so we can offer this service at a much reduced price compared to microinjection. The downside is that only small pieces of DNA (<200bp) can penetrate the embryo using this approach. It is a great choice for tags and point mutations. A way to avoid the small size limitation for larger knockin models is to package your DNA template into AAV which can handle up to ~4.5kb fragments. Go to prices

Embryo microinjection is the traditional way to introduce DNA templates with or without CRISPR reagents into mouse embryos. In the hands of experienced microinjectionists such as we have at the Hopkins Transgenic Core it is a way to reliably introduce a wide range of mutations. However, even with the best microinjectionists, more embryos tend to be needed to create the desired mutation leading to higher costs. Additionally, the number of embryos needed tends to increase with the size of the knockin leading to our 2 tiered price scale. For knockins up to ~4kb , AAV electroporation is a faster and cheaper option. Go to prices

Genetically engineered models are expensive to make. Once made, effort should be made to secure the line from the various calamities that can arise (mismanagement or genotyping error, animal room disaster, global pandemics, and genetic drift altering the original phenotype to name a few). Additionally, animal housing is expensive and is likely to become even more so. Cryopreservation is a way to safeguard your valuable mutant line and allow you to safely discontinue housing lines you don’t currently need. The Hopkins Transgenic Core offers both sperm and embryo cryopreservation services. Go to prices

Sperm Cryopreservation is the most commonly used way to cryogenically secure your line. The current protocols are extremely reliable for most mouse strains including C57BL/6. This is the recommended choice for any line that contains a single mutation locus on a common strain. The major advantage is that only one or two breeding aged males (10-16wks) are required. Our service includes the freeze as well as an IVF quality control test to ensure that sperm is viable and 3 years storage. Go to prices

Embryo cryopreservation is a reliable way to secure your line. Embryos have been stored for many decades and recovered including lines stored up to 20 years (so far) here at the Hopkins Transgenic Core. However, this approach has the big downside that it requires a lot more animals than sperm freezing. Sometimes as many as 10 or 20 females are needed to reach a safe number of embryos frozen. For this reason, this approach is mostly used for archiving lines that consist of several unlinked mutation loci. We charge a per session charge for this service due to the wide variation in the number of embryos obtained from mutant females. The minimum recommended number of embryos to consider your line safely archived is 200. Our service includes freezing a test straw to thaw as a quality control and 3 years of storage. Go to prices

IVF involving fresh or frozen sperm has several uses. The most common use is to recover a line from frozen sperm. This can be sperm frozen from your own line that you want to recover or sperm imported from another institution. A very useful byproduct of using IVF with imported sperm is that the resultant mice are free of all pathogens and thus this allows the importation of a line that is considered to be unsafe to import as a live animal.

Another common use of IVF is to rescue a line in which a mutant male has stopped breeding. Old males usually continue to make sperm long after they have lost interest in mating. We have recovered lines by obtaining sperm from males as much as 2 years old. Success is not guaranteed however as infertility in old males or in some mutant line can be due to loss of sperm production. Go to prices

Embryo importation is another way to import lines from other institutions. We have a great deal of experience with recovering lines from frozen embryos. However, in our experience, we have found sperm is a more reliable way to recover a line from shipped material so recommend this approach where it is available. Go to prices