Cosegregation of open-angle glaucoma and the nail-patella syndrome.
OBJECTIVE
To evaluate two families ascertained only for the presence of glaucoma in which both nail-patella syndrome and glaucoma occur in several generations and to determine whether the two diseases are genetically related.


METHODS
Ophthalmologic examinations and orthopedic examinations were performed. DNA samples from family members were screened with a microsatellite repeat marker at the argininosuccinate synthetase (ASS) locus at 9q34, and linkage analysis was performed.


RESULTS
Six patients with open-angle glaucoma were found among 13 patients with nail-patella syndrome in family UM:47. Seven patients with glaucoma were found among 11 patients with nail-patella syndrome in family UM:65. In both families, all individuals with glaucoma also had nail-patella syndrome. Two-point linkage analysis resulted in a lod score of 2.98 at a recombination fraction of 0.00 for open-angle glaucoma and nail-patella syndrome.


CONCLUSIONS
Linkage results presented here provide strong evidence that the orthopedic and nail anomalies in these two families result from the same nail-patella syndrome locus that has been previously linked to markers at 9q34. These data provide indirect evidence for a possible glaucoma locus at 9q34 and do not allow us to distinguish whether the glaucoma is the result of the nail-patella syndrome mutation or whether there is a separate locus responsible for glaucoma in these families. These studies suggest a need for ophthalmologic examination of individuals with nail-patella syndrome.
Lichter
P R
PR
Department of Ophthalmology, University of Michigan, Ann Arbor 48105, USA. plichter@umich.edu
Richards
J E
JE
Downs
C A
CA
Stringham
H M
HM
Boehnke
M
M
Farley
F A
FA
D000368:Aged; D000369:Aged, 80 and over; D001124:Argininosuccinate Synthase / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9; D004247:DNA / Q000235:genetics; D005260:Female; D008040:Genetic Linkage; D005902:Glaucoma, Open-Angle / Q000150:complications* / Q000235:genetics*; D006801:Humans; D008126:Lod Score; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D009261:Nail-Patella Syndrome / Q000150:complications* / Q000235:genetics*; D010375:Pedigree; D010641:Phenotype
D004247:DNA; D001124:Argininosuccinate Synthase