title: A North Carolina macular dystrophy phenotype in a Belizean family maps to the MCDR1 locus.
abstract: OBJECTIVE
  To describe the clinical findings of an autosomal dominant macular dystrophy in a family of Mayan Indian ancestry in Belize, Central America, and to determine its molecular genetic relationship with the original North Carolinian family.
  
  
  METHODS
  We performed comprehensive ophthalmic examinations on 56 members of a single family living in Chicago, Illinois, and Belize, Central America. Fundus photography and fluorescein angiography were performed on 17 affected subjects and six affected family members were serially examined over a 12-year period. Blood was collected from 26 individuals, and DNA was extracted for genotyping. Two-point linkage, multipoint linkage, and haplotype analysis was performed.
  
  
  RESULTS
  In 17 affected individuals, the clinical features were consistent with the diagnosis of North Carolina macular dystrophy. Multipoint linkage analysis generated a peak lod score of 5.6 in the MCDR1 region. The haplotype associated with the disease was, however, different from that of the original North Carolinian family.
  
  
  CONCLUSIONS
  This family has an autosomal dominant macular dystrophy that is clinically indistinguishable from North Carolina macular dystrophy (MCDR1). Our findings indicate that the mutated gene in this Belizean family maps precisely to the same region as that of the North Carolina macular dystrophy (MCDR1) locus. This study provides evidence that MCDR1 occurs in various ethnic groups and that there is no evidence of genetic heterogeneity.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago College of Medicine, USA.
authors.forename: M F
authors.initials: MF
authors.lastname: Rabb
authors.forename: L
authors.initials: L
authors.lastname: Mullen
authors.forename: S
authors.initials: S
authors.lastname: Yelchits
authors.forename: N
authors.initials: N
authors.lastname: Udar
authors.forename: K W
authors.initials: KW
authors.lastname: Small
mesh_terms: D000293:Adolescent; D000328:Adult; D001531:Belize; D002648:Child; D002675:Child, Preschool; D002874:Chromosome Mapping; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D004247:DNA / Q000032:analysis; D005260:Female; D005451:Fluorescein Angiography; D005654:Fundus Oculi; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D007197:Indians, Central American / Q000235:genetics; D007223:Infant; D008268:Macular Degeneration / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009657:North Carolina; D010375:Pedigree; D010641:Phenotype
chemical_list: D004247:DNA