From its first description in antiquity, the place of cryptophthalmos in the history of medical genetics is briefly set out until, in the twentieth century, this rare constellation of multiple congenital malformations of which cryptophthalmos is the most striking, even though not obligatory, component, was identified as an inherited autosomal recessive condition. It was given the name of Fraser syndrome and mutant alleles of the genes FRAS1, FREM2 and GRIP1 were identified as being responsible for a proportion of cases. In the remainder of cases, it may be supposed that mutant alleles of other genes, as yet unidentified, are responsible. In general, this association of multiple disparate malformations in an autosomal recessive condition may be expected to throw light on important aspects of gene action in embryogenesis. An aspect of medical genetics, which has become important with respect to the condition, is antenatal diagnosis with the prospect of abortion of affected fetuses.