This Mecp2 knockout strain is a mouse model of human Rett Syndrome. Mecp2-deficient males (Mecp2-/Y) exhibit mobility problems and a range of Rett Syndrome-like characteristics at 3-8 weeks of age. Heterozygous females exhibit a much later onset (~6 months of age).
Our preclinical efficacy testing services offer scientific expertise and an array of target-based and phenotype-based outcome measures, both in vivo and at endpoint, for flexible study designs and assay development in mouse models of Rett Syndrome. See our full service platform.
Adrian Bird, University of Edinburgh
Genetic Background | Generation |
---|---|
N4+N36pN5
|
Allele Type | Gene Symbol | Gene Name |
---|---|---|
Targeted (Null/Knockout) | Mecp2 | methyl CpG binding protein 2 |
Starting at:
$205.90 Domestic price for female 4-week |
232.12 Domestic price for breeder pair |
The Mecp2 knockout mutation is X-linked; therefore the Mecp2-deficient mice are Mecp2-/- (homozygous) females and Mecp2-/Y (hemizygous) males.
Mecp2 null mice are viable and appear normal at birth. No Mecp2 gene product (mRNA or protein) is detected in tissues. Mobility problems are apparent at 3-8 weeks of age. Mice exhibit hindlimb clasping and uneven breathing. An uneven wearing of teeth associated with misalignment of the jaws is observed in 50% of the animals. Adult males do not mate and their testes remain internal although sperm are present in the cauda epididymis. Symptom progression is variable, but mice can be expected to undergo weight loss, shivering, continued mobility problems before succumbing. Expected lifespan is approximately 50-60 days.
Heterozygous female mice display mobility problems and hindlimb clasping starting at about 6 months, but the symptoms are reported not to be progressive.
This Mecp2 knockout strain is useful for studying Rett Syndrome.
The Jackson Laboratory maintains this strain by breeding females heterozygous for the X-linked Mecp2 knockout mutation with C57BL/6J males. It has been our experience that less than 1% of all offspring genotype as "homozygous" females (120 of 36,437 females; July 2020). A cohort of "homozygous" females examined for karyotype were found to be XO. In general, the "homozygous" females present much the same as hemizygous males, with obesity, hind limb clasping, gradual decline in hind limb mobility and death between 50-100 days of age. In addition, rare instances of an obese heterozygous female has also been noted in the colony, which could possibly represent the same phenomenon. When identified in our colony, "homozygous" females are removed and the breeding unit that produced it is discontinued.
Importation of this model was supported in part by the Rett Syndrome Research Foundation.
A targeting vector was designed to insert loxP sites around exons 3 and 4 of the methyl CpG binding protein 2 gene (Mecp2) on the X chromosome. The construct was transfected into 129P2/OlaHsd-derived E14TG2a embryonic stem (ES) cells. Correctly targeted ES cells were injected into C57BL/6 blastocysts. Chimeric offspring were bred to C57BL/6 mice to produce heterozygous floxed females. The floxed line was bred to homozygosity and maintained in this form. Homozygous floxed female mice were crossed with male CMV-Cre mice (BALB/c background) in which the Cre gene is located on the X chromosome and is ubiquitously expressed. The resulting female mice, heterozygous for the germline recombined null allele, were mated with wild type C57BL/6 animals. Each subsequent generation of heterozygous females have been mated to inbred C57BL/6 males to maintain the line.
Allele Name | targeted mutation 1.1, Adrian Bird |
---|---|
Allele Type | Targeted (Null/Knockout) |
Allele Synonym(s) | Mecp2-; MeCP2Bird; Mecp2tm1+1Bird; Mecp2tm1-1Bird |
Gene Symbol and Name | Mecp2, methyl CpG binding protein 2 |
Gene Synonym(s) | |
Strain of Origin | 129P2/OlaHsd |
Chromosome | X |
Molecular Note | Insertion of a neomycin resistance cassette into the Mecp2 gene introduced loxP sites that flank exons 3 and 4, and added an intron and polyadenylation signal from the human beta globin gene. A CMV-Cre mediated recombination event in the germline then removed exons 3 and 4. Northern blot analysis did not detect Mecp2 mRNA in tissues of mutant male mice (-/y), nor did Western blot analysis detect protein in these tissues. |
Mutations Made By | Adrian Bird, University of Edinburgh |
The Mecp2 knockout mutation is X-linked; therefore the Mecp2-deficient mice are Mecp2-/- (homozygous) females and Mecp2-/Y (hemizygous) males.
When maintaining a live colony at The Jackson Laboratory, heterozygous females are bred to C57BL/6J inbred males (Stock No. 000664). Heterozygous females breed best when under 6 months of age. Coat color expected from breeding is black.
When using the Mecp2- mouse strain in a publication, please cite the originating article(s) and include JAX stock #003890 in your Materials and Methods section.
Service/Product | Description | Price |
---|---|---|
X linked - Heterozygous Females and Wild-type Males for Mecp2<tm1.1Bird> |
Terms are granted by individual review and stated on the customer invoice(s) and account statement. These transactions are payable in U.S. currency within the granted terms. Payment for services, products, shipping containers, and shipping costs that are rendered are expected within the payment terms indicated on the invoice or stated by contract. Invoices and account balances in arrears of stated terms may result in The Jackson Laboratory pursuing collection activities including but not limited to outside agencies and court filings.
The Jackson Laboratory has rigorous genetic quality control and mutant gene genotyping programs to ensure the genetic background of JAX® Mice strains as well as the genotypes of strains with identified molecular mutations. JAX® Mice strains are only made available to researchers after meeting our standards. However, the phenotype of each strain may not be fully characterized and/or captured in the strain data sheets. Therefore, we cannot guarantee a strain's phenotype will meet all expectations. To ensure that JAX® Mice will meet the needs of individual research projects or when requesting a strain that is new to your research, we suggest ordering and performing tests on a small number of mice to determine suitability for your particular project. We do not guarantee breeding performance and therefore suggest that investigators order more than one breeding pair to avoid delays in their research.
What information were you hoping to find through your search?
How easy was it to find what you were looking for?
We may wish to follow up with you. Enter your email if you are happy for us to connect and reachout to you with more questions.
Please Enter a Valid Email Address
Thank you for sharing your feedback! We are working on improving the JAX Mice search. Come back soon for exciting changes.