A locus for isolated cataract on human Xp.
OBJECTIVE
To genetically map the gene causing isolated X linked cataract in a large European pedigree.


METHODS
Using the patient registers at Birmingham Women's Hospital, UK, we identified and examined 23 members of a four generation family with nuclear cataract. Four of six affected males also had complex congenital heart disease. Pedigree data were collated and leucocyte DNA extracted from venous blood. Linkage analysis by PCR based microsatellite marker genotyping was used to identify the disease locus and mutations within candidate genes screened by direct sequencing.


RESULTS
The disease locus was genetically refined to chromosome Xp22, within a 3 cM linkage interval flanked by markers DXS9902 and DXS999 (Zmax=3.64 at theta=0 for marker DXS8036).


CONCLUSIONS
This is the first report of a locus for isolated inherited cataract on the X chromosome. The disease interval lies within the Nance-Horan locus suggesting allelic heterogeneity. The apparent association with congenital cardiac anomalies suggests a possible new oculocardiac syndrome.
Francis
P J
PJ
Department of Molecular Genetics, Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.
Berry
V
V
Hardcastle
A J
AJ
Maher
E R
ER
Moore
A T
AT
Bhattacharya
S S
SS
D000293:Adolescent; D000328:Adult; D000368:Aged; D002386:Cataract / Q000235:genetics*; D002648:Child; D002874:Chromosome Mapping / Q000379:methods; D005260:Female; D008040:Genetic Linkage / Q000235:genetics; D005819:Genetic Markers / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D010641:Phenotype; D014960:X Chromosome / Q000235:genetics*
D005819:Genetic Markers