We report here a novel X-linked mutant, named faint lined (Fnl),
which was discovered in the
litter of an irradiated 3H1 male (Dr Bruce Cattanach, personal communication).
The mutation is
associated with fine dorsal striping in affected heterozygous females and
prenatal lethality in males.
Approximately 50% of Fnl/+ females die in utero and
surviving animals have a reduced weight at
birth and weaning. Histological studies failed to reveal the underlying
basis of the phenotype or
any gross structural abnormalities in internal organs (Fnl/+×Mus
spretus) F1 affected females
were backcrossed to 3H1 males and haplotype analysis positioned Fnl
in the proximal region of
the mouse X chromosome distal to Ant2 and proximal to Hprt.
Therefore, Fnl lies within a defined
conserved segment and its human homologue can be predicted to lie in the
in Xq25. Further genetic resolution of co-segregating markers flanking
Fnl established that Fnl lies
in a 7·6±2·6 cM interval between DXMit50