Biomedical Engineering Reference
In-Depth Information
Dvl1
Dvl2
Cranio
-rachishisis
Organ of Corti
Conotruncal
defects
Nodal cilia
Polarity defects
Gastrulation
defects
Conotruncal defects (50%)
Skeletal defects (100%)
Spina bifida (2-3%)
Social abnormalities
Sensorimotor gating
defects
Cranio
-rachishisis
Posterior
truncation
Midgestation
lethality
Vascular?
Conotruncal defects (100%)
Organ of Corti defects
Xiphoid bifurcation
Dvl3
Figure 9.1 Summary of single, double, and triple
mutant phenotypes in the form of
a Venn diagram. The single gene knock-out phenotypes are illustrated by the large cir-
cles. The major double- and triple-mutant phenotypes are shown in the intersection of
two or three circles, respectively. See text for details.
Dvl
6. DVL1 NULL MICE: SOCIAL INTERACTION DEFECTS
Mice completely deficient for
Dvl1
are viable, fertile, and structurally
normal. Surprisingly, these mice exhibited reduced social interaction and were
the first mutant organism of any species that displayed social behavior deficits
(
Lijam et al., 1997
). When examining offspring housed as uniform genotypes,
we noticed that most (50-75%) wild-type 129SvEv mice were completely de-
void of whiskers and had trimmed facial hair. Whisker-trimming or barbering
is a social behavior characteristic of several caged wild-type mouse strains, and
129SvEv mice (Taconic Farms) displayed this severe whisker-trimming
behavior. In contrast, all 129SvEv
Dvl1
-deficient mice (100%) had full sets
of whiskers and facial hair, while
Dvl1
รพ
/
mice had trimmed whiskers. By
video recording wild-type and mutant mice, we confirmed that whisker-
trimming was a social behavior that was defective in
Dvl1
/
mice.
To examine whether differences in social interaction were responsible for
differences in whisker-trimming behavior, we combined one wild-type mouse,
devoid of whiskers and facial hair, and one
Dvl1
/
mouse, with full facial
