Br J Ophthalmol 1999;83:919-922
( August )
Phenotype of autosomal recessive congenital microphthalmia
mapping to chromosome 14q32
David A R Bessanta b, Khalid Anwarc, Shagufta Khaliqc, Abdul Hameedc, M Ismailc, Annette M Paynea, S Qasim Mehdic, Shomi S Bhattacharyaa
a Department of
Molecular Genetics, Institute of Ophthalmology, London, b Moorfields Eye Hospital, London, c Dr A Q Khan Research Laboratories,
Biomedical and Genetic Engineering Division, Islamabad, Pakistan
Correspondence to: David A R Bessant,
Department of Molecular Genetics, Institute of Ophthalmology, London
EC1V 9EL.
Accepted for publication 8 March 1999
BACKGROUND
Congenital
microphthalmia (OMIM: 309700) may occur in isolation or in association
with a variety of systemic malformations. Isolated microphthalmia may
be inherited as an autosomal dominant, an autosomal recessive, or an X
linked trait.
METHODSBased on a
whole genome linkage analysis, in a six generation consanguineous
family with autosomal recessive inheritance, the first locus for
isolated microphthalmia was mapped to chromosome 14q32. Eight members
of this family underwent clinical examination to determine the nature
of the microphthalmia phenotype associated with this locus.
RESULTSAll affected
individuals in this family suffered from bilateral microphthalmia in
association with anterior segment abnormalities, and the best visual
acuity achieved was "perception of light". Corneal changes included
partial or complete congenital sclerocornea, and the later development
of corneal vascularisation and anterior staphyloma. Intraocular
pressure, as measured by Schiotz tonometry, was greatly elevated in
many cases.
CONCLUSIONSThis
combination of ocular defects suggests an embryological disorder
involving tissues derived from both the neuroectoderm and neural crest.
Other families with defects in the microphthalmia gene located on 14q32
may have a similar ocular phenotype aiding their identification.
© 1999 by British Journal of Ophthalmology
