Localization of a recessive juvenile cataract mutation to proximal chromosome 7 in mice.
OBJECTIVE
To localize the chromosomal position of a novel cataract mutation (juvenile recessive cataract; jrc) in mice.


METHODS
A mapping population was developed by crossing cataract males (albino MH) to wild-type females (black C57BL/6J). F1 females were backcrossed to albino MH males with cataracts.


RESULTS
The results were consistent with a model of a single autosomal recessive gene [153 cataract, 169 wild-type; chi2 = 0.8, 1 degree of freedom (d.f.), p > 0.35]. Linkage with the albino (tyrosinase; Tyr) locus was evident (chi2 = 61.5, 1 d.f., p < 0.0001), implicating chromosome 7 as the location of jrc. Recombination percentages (+/- SE) between jrc and D7Mit340 (1.2 cM location), D7Mit227 (16.0 cM) and D7Mit270 (18.0 cM) were 17.1 +/- 2.1, 3.7 +/- 1.1 and 6.2 +/- 1.3%, respectively. Multi-point mapping determined that the most likely order of these loci is D7Mit340 - jrc - D7Mit227 - D7Mit270 - Tyr. Although animals with the mutant phenotype appeared to have little or no sense of sight, their growth was not different (p >0.20) from that of normal mice.


CONCLUSIONS
The jrc mutation model may be useful in the study of the genetics of cataracts in other animal species, including humans.
Cargill
E J
EJ
Department of Animal Science, University of Nebraska, Lincoln, Nebr 68583-0908, USA.
Happold
T R
TR
Bertani
G
G
Rocha
J
J
Lou
M F
MF
Pomp
D
D
Nielsen
M K
MK
D000818:Animals; D002386:Cataract / Q000235:genetics*; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D005260:Female; D005808:Genes, Recessive; D005819:Genetic Markers; D006200:Hair Color / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation
D005819:Genetic Markers