Mitral Valve Prolapse 3

Description

Patients with mitral valve prolapse-3 (MVP3) have nonsyndromic MVP of variable severity with an autosomal dominant pattern of inheritance.

For a general phenotypic description and discussion of genetic heterogeneity of mitral valve prolapse, see MVP1 (157700).

Clinical Features

Nesta et al. (2005) studied a family in which multiple members in 3 generations had echocardiographic findings consistent with MVP. By clinical evaluation, Marfan syndrome and other connective tissue disorders were excluded.

Mapping

By genotypic analyses with polymorphic microsatellite markers in a 3-generation family segregating MVP, Nesta et al. (2005) found evidence of linkage of the disorder to 13q31.3-q32.1, with a nonparametric linkage score of 18.41 (p less than 0.0007). Multipoint parametric analysis gave a lod score of 3.17 at marker D13S132. All 9 fully diagnostic MVP family members shared the same locus haplotype and 5 of 6 family members with mitral valve morphologies not meeting diagnostic criteria but resembling fully developed forms carried all or part of the haplotype. A prodromal morphology was seen in 2 family members carrying the haplotype, consisting of anterior displacement of the coaptation point along the mitral annulus and bulging of the posterior leaflet relative to the anterior.