Fine mapping of the Schnyder?s crystalline corneal dystrophy locus

Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA.
Human Genetics (Impact Factor: 4.52). 06/2004; 114(6):594-600. DOI: 10.1007/s00439-004-1110-1
Source: PubMed

ABSTRACT Schnyder's crystalline corneal dystrophy (SCCD) is a rare autosomal dominant eye disease with a spectrum of clinical manifestations that may include bilateral corneal clouding, arcus lipoides, and anterior corneal crystalline cholesterol deposition. We have previously performed a genome-wide linkage analysis on two large Swede-Finn families and mapped the SCCD locus to a 16-cM interval between markers D1S2633 and D1S228 on chromosome 1p36. We have collected 11 additional families from Finland, Germany, Turkey, and USA to narrow the critical region for SCCD. Here, we have used haplotype analysis with densely spaced microsatellite markers in a total of 13 families to refine the candidate interval. A common disease haplotype was observed among the four Swede-Finn families indicating the presence of a founder effect. Recombination results from all 13 families refined the SCCD locus to 2.32 Mbp between markers D1S1160 and D1S1635. Within this interval, identity-by-state was present in all 13 families for two markers D1S244 and D1S3153, further refining the candidate region to 1.58 Mbp.

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    • "The recruitment efforts which spanned from 1987 to the present have been described in prior publications [Shearman et al., 1996; Theendakara et al., 2004] with Institutional Review Board approval of the study obtained from University of Massachusetts Medical Center from 1992 to 1995 and subsequently from Wayne State University to the present. Written informed consent was obtained from all adults and the parents of minors under research tenets of the Declaration of Helsinki. "
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