Fraser syndrome (also known as Meyer-Schwickerath's syndrome, Fraser-François syndrome, or Ullrich-Feichtiger syndrome) is an autosomal recessive congenital disorder, identified by several developmental anomalies. Fraser syndrome is named for the geneticist George R. Fraser, who first described the syndrome in 1962. Signs and symptoms It is characterized by developmental defects including cryptophthalmos (where the eyelids fail to separate in each eye), and intersex development in the genitals (such as micropenis, or clitoromegaly) and cryptorchidism Congenital malformations of the nose, ears, larynx and renal system, as well as developmental delays, manifest occasionally. Syndactyly (fused fingers or toes) has also been noted. Genetics The genetic background of this disease has been linked to a gene called FRAS1, which seems to be involved in skin epithelial morphogenesis during early development. It has also been associated with FREM2 and with GRIP1. Mapping By autozygosity mapping, McGregor et al. (2003) located the Fraser syndrome locus to chromosome 4q21. Genetic Heterogeneity In 6 of 18 consanguineous families with Fraser syndrome, van Haelst et al. (2008) excluded linkage to both the FRAS1 and FREM2 genes, indicating genetic heterogeneity. Molecular genetics In 5 families with Fraser syndrome, McGregor et al. (2003) identified 5 homozygous mutations in the FRAS1 gene (e.g., 607830.0001), which encodes a putative extracellular matrix (ECM) protein. In 2 families with Fraser syndrome unlinked to the FRAS1 gene, Jadeja et al. (2005) found a homozygous missense mutation in the FREM2 gene (608945.0001). In an infant girl with Fraser syndrome, Slavotinek et al. (2006) identified compound heterozygosity for a deletion (607830.0006) and an insertion (607830.0007) in the FRAS1 gene, inherited from her mother and her father, respectively. Cavalcanti et al. (2007) described 2 stillborn Brazilian male siblings, born at 25 and 29 weeks' gestation, respectively. One sibling appeared to have a lethal form of ablepharon-macrostomia syndrome (AMS; 200110) or an intermediate phenotype between AMS and Fraser syndrome, and the other had classic Fraser syndrome. Analysis of the FRAS1 gene revealed homozygosity for a splice site mutation (607830.0008), resulting in a severely truncated protein in both siblings and heterozygosity for the mutation in both parents. Cavalcanti et al. (2007) concluded that a phenotype resembling AMS is a rare clinical expression of Fraser syndrome, with no obvious genotype/phenotype correlation. In a female fetus with a normal karyotype and cryptophthalmos, ambiguous external genitalia, syndactyly, bilobed lungs, bilateral renal agenesis, hypoplastic bladder, and agenesis of internal genitalia with streak ovaries, Shafeghati et