Familial high myopia: evidence of an autosomal dominant mode of inheritance and genetic heterogeneity. |
| |
Authors: | L Naiglin J Clayton C Gazagne F Dallongeville F Malecaze P Calvas |
| |
Institution: | Laboratoire d'Immuno-Génétique moléculaire, Université Paul Sabatier, H?pital Purpan, Pavillon Charles Lefebvre, Toulouse, France. |
| |
Abstract: | High myopia, defined as a refractive error inferior to -6 diopters, often appears as a familial disease. In order to precise its genetic background, we performed a segregation analysis on 32 French families (320 subjects including 120 individuals with clinical data) containing at least one high myopic person in their genealogy. Under the assumption of a two-alleles single gene model, the autosomal dominant transmission mode showed a much greater likelihood than the autosomal recessive mode, which therefore was rejected. From the segregation model obtained, a two-point linkage analysis was made on 18 families (107 subjects), among the 32 used for the segregation analysis. Different candidate loci were tested: collagen genes including Stickler syndrome types 1 and 2, proteoglycan genes, Marfan 1 syndrome and a Marfan like disorder localised in 3p24.2-p25. No evidence of linkage was found with any of the studied markers. In addition, the absence of linkage with chromosome 18p11.31 markers, a locus linked to familial high myopia in 6 North American families and 1 family of Chinese descent, demonstrated the genetic heterogeneity of the disease. |
| |
Keywords: | |
|
|