A mutation in identified as a probable cause for autosomal recessive Peters anomaly in a consanguineous family.

PURPOSE

Peters anomaly (PA) is a heterogeneous developmental disorder characterized by central corneal opacity and iridocorneal or corneolenticular adhesions. Although many causative genes have been identified, most screened patients do not have mutations in the known genes. We aimed to identify the genetic cause of Peters anomaly in a pedigree with three affected individuals.

METHODS

Slit-lamp biomicroscopy and ultrasound biomicroscopy were performed for definitive diagnosis. Exome sequencing was conducted on the DNA of all three patients. After identification of a candidate causative gene, expression of the gene was assessed with real-time PCR in various ocular tissues of three human embryos and three adults.

RESULTS

The patients were affected with isolated PA. The parents of the patients were related to one another. Inheritance of PA was autosomal recessive. After appropriate filtering of the exome data, a homozygous variation in remained as the only candidate genetic cause of PA in the pedigree. The variant segregated with disease status in the pedigree and was absent among 800 control Iranians. The variant has been reported in various databases at frequencies of 0.006 or less only in the heterozygous state in some cohorts of African origin. The p.Val1660 amino acid affected by the mutation is completely conserved in mammals and birds during evolution. Expression of was shown in all adult and embryonic lens, iris, cornea, sclera, and retina tissues that were tested.

CONCLUSIONS

that encodes DOP1 leucine zipper like protein B was identified as the putative PA-causing gene in pedigree PA-101. As is positioned within the Down syndrome chromosomal region on chromosome 21, until now this gene has mostly been studied with respect to brain functions. However, members of the gene family have been shown to have roles in development in other organisms. Evidence of the expression of in various PA-relevant eye tissues, which, to the best of our knowledge, is shown here for the first time, is to be noted. However, this finding does not necessarily implicate a specific role for in eye development as the gene is expressed in many tissues. Ultimately, definitive assessment of the contribution of to PA pathology awaits identification of mutations in the gene in unrelated patients with PA and functional studies.