Towards identification of genes in regionally accumulated strabismus

Strabismus, as an inherited disease, is a new challenge to the geneticist. Various forms of strabismus can be found in distantly related members of the same family, who usually report to local ophthalmologists and orthoptic centers very rarely. In addition, local ophthalmologists and orthoptic centers very rarely pay attention to the genetic aspects of strabismus. Therefore, the recruitment of suitable families to identify the underlying genes is the major drawback in this effort. Further problems arise from the mode of inheritance, which can formally be characterized as autosomal dominant with reduced penetrance in most families, but should be considered as multifactorial inheritance with a threshold combination of mutated alleles. The present paper deals with a method for using local accumulations of strabismus patients to circumvent the problems of small families and rare numbers of affected persons. The steps on the way to the identification of strabismus genes will be described.