FVB.129P2(B6)-Fmr1^tm1Cgr/J

Stock number: 003024
Product name: Fmr1 KO
Research areas: Developmental Biology Research, Mouse/Human Gene Homologs, Neurobiology Research

Description

These Fmr1 knockout mice may be useful in applications related to the study of Fragile X Syndrome.

Detailed description

Mice homozygous for the Fmr1^tm1Cg targeted mutation show macroorchidism (enlarged testes), learning deficits, and hyperactivity. Macroorchidism in caused by an increased rate of Sertoli cell proliferation during embryogenesis which may be independent of FSH signalling. Comparison of homozygotes to wildtype littermates in hidden- and visible-platform water maze learning showed deficits in spatial learning and motor performance. This strain is homozygous for the retinal degeneration allele Pde6b^rd1.

Development

The targeted mutation was made in the laboratory of Dr. Ben Oostra at Erasmus University in the Netherlands by replacing exon 5 of the fragile X mental retardation syndrome 1 (Fmr1) gene with a neomycin resistance (neo) cassette. The construct was electroporated into 129P2/OlaHsd-derived E14 embryonic stem (ES) cells. Correctly targeted ES cells were injected to C57BL/6J blastocysts and resulting males were bred to C57BL/6J females. These mice were backcrossed to FVB/N mice for an unknown number of generations. Upon arrival at The Jackson Laboratory, these mice were bred to FVB/NJ (Stock No. 001800) mice for at least 5 generations.

Allele

Symbol: Fmr1^tm1Cgr
Name: targeted mutation 1, Ben Oostra
MGI accession ID: MGI:1857169
Generation method: Targeted
Attributes: Null/Knockout
Synonyms: fmr-tm1Cgr; FraX; Fmr1 KO; FMRP KO; Fmr1^tm4Cgr
Marker symbol: Fmr1
Marker name: fragile X mental retardation 1
Chromosome: X
Strain of origin: 129P2/OlaHsd
Molecular note: A neomycin resistance gene was inserted into exon 5. RT-PCR analysis on testis RNA derived from hemizygous male mice demonstrated that no detectable transcript was produced from this allele, and western blot analysis on extracts of testes, liver, kidney and brain of hemizygous male mice confirmed that no stable encoded protein was made.
General note: Genbank: AF179463 and AF170530