International Mammalian Genome Society

The 16th International Mouse Genome Conference (2002)

Plenary Presentations * Oral Presentations *
Poster Presentations: Complex Genetics and Disease Modifiers * Developmental Genetics * Functional Genomics * Gene Discovery * Genetic Manipulations to Alter Gene Function * Mouse Models: Human Disease and Pharmacogenetics * Sequence Annotation and Comparative Analysis of Genomes *
Attendees * Sponsors * Table of Contents * Photographs * Awards

POSTER 141 - BAT: A NOVEL RECESSIVE MUTATION AFFECTING THE EYELID AND CORNEAL EPITHELIUM

X Du
The Scripps Research Institute

Whitten C, Mann N, Beutler B
The Scripps Research Institute

Through germline saturation mutagenesis with N-ethyl-N-nitrosourea (ENU) in C57BL/6J mice, we have produced a novel mutation affecting development of the eye. This recessive mutation, named bat, is characterized by eyelid fusion (ankyloblepharon) and a complete lack of corneal, conjunctival and eyelid epithelium. The phenotype closely mimics non-syndromic cryptophthalmos with ankyloblepharon, a rare inherited human disease. In bat homozygotes, the dermis of the eyelid is fused to the corneal stroma, and in most cases, the palpebral fissure is absent.  On the C57BL/6J background, the mutant phenotype is occasionally accompanied with microphthalmia. The mice are otherwise phenotypically normal, suggesting that the gene in question has a highly specific function:  to generate and/or to maintain the corneal epithelium. It has been known that the corneal epithelium arises in embryo from a monolayer of ectoderm that lies over the corneal stroma, and is constantly replenished by a population of stem cells that reside at the cornea limbus. Hence, bat provides an excellent model system to study the genetic program that creates a clearly defined stem cell population, and suggests that epithelia of the cornea, conjunctiva, and lids arise from a single primordium. Bat is currently being mapped for positional isolation.  The pattern of bat expression during development, and its effect on differentiation and maintenance of limbal cells will then be addressed.