The majority of mice homozygous for the Igf1tm1Tstargeted mutation die perinatally. Only ~4% of homozygotes survive beyond birth for up to 4 months of age. Heterozygotes have serum levels of IGF-1 that are 37% lower than in wild type mice. Body size is, proportionally, 10-20% smaller than that of normal wild type siblings, with no apparent histological abnormalities.
|Allele Name||targeted mutation 1, Timothy Stewart|
|Allele Type||Targeted (Null/Knockout)|
|Gene Symbol and Name||Igf1, insulin-like growth factor 1|
|Strain of Origin||129S7/SvEvBrd-Hprt+|
|Molecular Note||A neomycin selection cassette was inserted into exon 3 after codon 15. This mutation inserts multiple stop codons into all reading frames of the B chain of the encoded protein. RT-PCR analysis demonstrated that the transcript is undetectable in homozygous animals.|
|Mutations Made By|| |
Dr. Timothy Stewart
This strain was generated on a 129 genetic background. It was crossed to C57BL/6, and since has been backcrossed 6 times to CD1. The donating laboratory maintained the strain by mating heterozygous siblings.
When using the IGF-1 KO mouse strain in a publication, please cite the originating article(s) and include JAX stock #003258 in your Materials and Methods section.