These mice carry the spontaneous Lse mutation and are characterized by abnormal external ear formation and eye defects along with retarded growth and shortened life span.Read More +
Lse/+ pups can be identified at birth by the presence of an open auditory meatus, which in normal mice remains closed until approximately day 13, when the eyes also open. Fewer than the expected 50% affected pups are born, and about 50% of pups identified as Lse/+ fail to survive until weaning. Homozygotes either die prenatally or are indistinguishable from heterozygotes.
The ears of Lse/+ mice are positioned lower and further forward than those of normal mice and are abnormally formed. These mice are not deaf. In addition to the ear abnormalities, Lse/+ mice are smaller than their normal littermates and have opaque corneas (Theiler and Sweet 1986).
Low set ears, Lse, is a dominant mutation first observed in a male pup from a cross between the recipient of an ovary transplant from a Lmx1adr-J/Lmx1adr-J female and a C3HeB/FeJLe-a/a male. Lse has been maintained since its discovery by crossing affected male or female mice at each generation with B6C3Fe-a/a (C57BL/6J X C3HeB/FeJLe-a/a) F1 hybrid mice (Theiler and Sweet 1986).
|Gene Symbol and Name||a, nonagouti|
|Strain of Origin||old mutant of the mouse fancy|
|General Note||Insertion of the LV30 retrotransposon without the beta4 retrovirus sequence does not cause the nonagouti phenotype. J:278039|
|Molecular Note||Characterization of this allele shows an insertion of DNA comprised of a 5.5kb virus-like element, VL30, into the first intron of the agouti gene. The VL30 element itself contains an additional 5.5 kb sequence, flanked by 526 bp of direct repeats (beta4 retroviral sequence). The host integration site is the same as for at-2Gso and Aw-38J and includes a duplication of four nucleotides of host DNA and a deletion of 2 bp from the end of each repeat. Northern analysis of mRNA from skin of homozygotes shows a smaller agouti message and levels 8 fold lower than found in wild-type.|
Comments: Culling normal littermates improves survival of Lse/+ pups (Theiler and Sweet 1986).
When using the low set ears mouse strain in a publication, please cite the originating article(s) and include JAX stock #001280 in your Materials and Methods section.