Evidence that a locus for familial high myopia maps to chromosome 18p.
Myopia, or nearsightedness, is the most common human eye disorder. A genomewide screen was conducted to map the gene(s) associated with high, early-onset, autosomal dominant myopia. Eight families that each included two or more individuals with >=-6.00 diopters (D) myopia, in two or more successive generations, were identified. Myopic individuals had no clinical evidence of connective-tissue abnormalities, and the average age at diagnosis of myopia was 6.8 years. The average spherical component refractive error for the affected individuals was -9.48 D. The families contained 82 individuals; of these, DNA was available for 71 (37 affected). Markers flanking or intragenic to the genes for Stickler syndrome types 1 and 2 (chromosomes 12q13.1-q13.3 and 6p21.3, respectively), Marfan syndrome (chromosome 15q21.1), and juvenile glaucoma (chromosome 1q21-q31) were also analyzed. No evidence of linkage was found for markers for the Stickler syndrome types 1 and 2, the Marfan syndrome, or the juvenile glaucoma loci. After a genomewide search, evidence of significant linkage was found on chromosome 18p. The maximum LOD score was 9.59, with marker D18S481, at a recombination fraction of .0010. Haplotype analysis further refined this myopia locus to a 7.6-cM interval between markers D18S59 and D18S1138 on 18p11.31.
Young
T L
TL
Department of Ophthalmology, University of Minnesota, Minneapolis, MN 55455, USA. young061@gold.tc.umn.edu
Ronan
S M
SM
Drahozal
L A
LA
Wildenberg
S C
SC
Alvear
A B
AB
Oetting
W S
WS
Atwood
L D
LD
Wilkin
D J
DJ
King
R A
RA
D002874:Chromosome Mapping; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics*; D005123:Eye / Q000473:pathology; D005260:Female; D005799:Genes, Dominant / Q000235:genetics; D008040:Genetic Linkage / Q000235:genetics*; D005901:Glaucoma / Q000235:genetics; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D008126:Lod Score; D008297:Male; D008382:Marfan Syndrome / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics; D009216:Myopia / Q000235:genetics*; D010375:Pedigree