B6 Albino A++

Targeted Replacement

B6 Albino A++ Targeted Replacement Mouse Model
EZcohort™ Models
The easiest way to acquire and breed cryopreserved GEMs

C57BL/6NTac Background

  • Model #
  • Genotype
  • Nomenclature
  • 11227-F
    C57BL/6NTac-Atm1.1Arte Tyrtm1Arte
  • 11227-M
    C57BL/6NTac-Atm1.1Arte Tyrtm1Arte
  • A new and improved B6 albino strain based on the C57BL/6NTac substrain.
  • Contains two mutations, a mutation in the Tyr gene to introduce albinism, and a reversion of the non-agouti (a) locus to the agouti locus (A)
  • Using the Taconic B6 Albino as a blastocyst host and mating the subsequent chimeras to a standard B6 mouse permits detection of ES cell germline transmission by coat color and ensures that the G1 animal is identical to the B6 genome at all coat color loci
  • The Taconic B6 albino is an ideal host for maintaining substrain specificity ES cells derived from the C57BL/6NTac substrain
  • Can also be used as a genetic background for models in which a B6 background is needed with an albino coat, for example in imaging applications
  • Available only from Taconic!
  • Please note that chimeras generated using B6-derived ES cells and blastocysts from the B6 Albino A++ will be tri-colored. The agouti signalling peptide (produced in blastocyst-derived cells, which appear albino in the chimera) can produce a paracrine signalling effect in some cells derived from the ES cells. ES cell-derived hair patches can thus be either black or agouti. Both black and agouti patches should be counted for determination of chimerism percentages.

Genetic Background:

C57BL/6NTac Background


The B6 Albino A++ model was developed by Taconic. In C57BL/6 mice, intron 1 of the agouti locus contains a retrotransposon which is responsible for the non-agouti phenotype. In the Taconic B6, the region containing this retrotransposon was replaced with a FRT-flanked neomycin-puromycin resistance cassette in C57BL/6NTac-derived ES cells via gene targeting. The constitutive knock out allele was then generated via Flp-mediated removal of the selection cassette. The Tyr mutation is a constitutive knock in of a point mutation in which a G nucleotide located at position 369 in exon 1 has been replaced with C nucleotide, resulting in an amino acid substitution at position 103 (Cys>Ser). The F3 site flanked selection marker was removed by via Flp recombinase. Mice containing the agouti and tyrosinase mutations were intercrossed, and then the line was intracrossed to homozygosity.


Use of the Taconic B6 Albino A++ in the following manner permits detection of ES cell germline transmission in a single step by coat color, with NO genotyping required!

Additionally, the germline progeny are identical to the C57BL/6 genome at all coat color loci!





Initial Publication:

Zevnik B, Uyttersprot NC, Perez AV, Bothe GW, Kern H, Kauselmann G. (2014) C57BL/6N albino/agouti mutant mice as embryo donors for efficient germline transmission of C57BL/6 ES cells. PLoS One. 2014 Mar 5;9(3):e90570.   

Conditions of Use for EZcohort™ Models
EZcohort™ models are produced and distributed under rights to patents and intellectual property licensed from various institutions. Taconic Biosciences, Inc. (Taconic) sells EZcohort™ models to purchasers, grants to each purchaser a right under Taconic's rights in such licensed patents and intellectual property to use the purchased EZcohort™ models in consideration of purchasers' acknowledgement of and agreement to Taconic's Terms and Conditions for the Sale of Products and the following conditions of use:

  • Title to EZcohort™ models and biological materials derived from them remains with Taconic.
  • EZcohort™ models will be used for research purposes only.
  • EZcohort™ models and biological materials derived from them will not be distributed to third parties or used for commercial purposes.
  • Breeders from deliverables can be used for propagation of EZcohort™ models or to cross to other strains.
  • Continuation of breeding and crossbreeding of EZcohort™ models outside Taconicis permitted for a term of three years post-purchase of the EZcohort™ models and is subject to annual confirmation of these EZcohort™ Conditions of Use.

Continuation of breeding and crossbreeding after the three year term will require renewal of the EZcohort™ Conditions of Use and payment of a fee.