The Tbx1 (T-box 1) gene belongs to a family of transcription factors involved in development. Mouse TBX1 shares 98% amino acid identity with the human ortholog. The gene is located in a region associated with DiGeorge syndrome(DGS)/velocardiofacial syndrome located on human chromosome 22q11.2.
These knock-out mice contain a loxP-flanked neomycin cassette that replaces the entire coding region of the gene with the exception of the first 20 amino acids. Homozygotes die at birth; late term embryos and neonatal mice appear edematous, small, have a shortened neck region, low-set abnormally folded or absent external ears, smaller and thickened otic vesicles, abnormal vertebrae, mandible and cleft palate. Most mice lack a thymus and parathryroid. Sublingual and submaxillary salivary glands are reduced or missing. Cardiovascular phenotype includes a single cardiac outflow tract, a single large aortic arch on each side, and a persistent truncus arteriosis. Embryos appear normal at E7.5, but become abnormal at the 13-15 somite stage. Pharnygeal arches and pouches fail to develop normally beyond the first arch and pouch.
Heterozygotes exhibit absence or reduction in thickness of the fourth aortic arch arteries at E11.5, no other abnormalities are observed. The phenotype is more severe on the 129 background.

These mice may be useful for studying DiGeorge syndrome.

This knock-out allele of Tbx1 (T-box 1) deletes almost the entire coding region, resulting in perinatal lethality. Embryos exhibit many features characteristic of DiGeorge syndrome including cardiac outflow tract abnormalities, thymic hypoplasia, abnormal facial structures, abnormal vertebrae and cleft palate. This strain may be useful for studying DiGeorge syndrome.

This strain is hosted by NIH's MMRRC, which partners with JAX for the distribution of this and other strains. For additional information and to purchase, please visit the MMRRC site.