Stickler Syndrome Type 2 and Linkage to the COL11A1 Genea

Stickler syndrome (hereditary arthro-ophthalmopathy) is an autosomal-dominant condition characterized by severe short sight, arthritis, deafness, flat facial appearance, cleft palate, and small chin.It is the commonest inherited cause of retinal detachment.There is genetic heterogeneity, with about two-thirds of cases caused by mutations in the gene encoding type I1 procollagen (COL2A1).We have recently shown that Stickler syndrome can be subclassified on the basis of vitreoretinal phenotype: type 1 families with a characteristic congenital vitreous anomaly show linkage without recombination to markers at the COL2A 1 locus; type 2 families with different congenital vitreoretinal phenotypes are not linked to COL2AI.lWe have now investigated linkage to other candidate genes in a large type 2 family with vitreoretinal, articular, orofacial, and audiometric features of Stickler syndrome.A maximum lod score of 2.7 at zero recombination was obtained with the marker DlS223, which is 2 cm from the COL 1 1 A 1 locus on chromosome 1.Linkage to COL2A 1, COL5A2, COL9A 1, CRTL I, and COL 1 1 A2 was excluded.Brunner et al.2 have recently re-