Microcoria due to first duplication of 13q32.1 including the GPR180 gene and maternal mosaicism.

Congenital microcoria (MCOR) is an eye anomaly characterized by a pupil with diameter below 2 mm, and is caused by underdevelopment or absence of the dilator muscle of the pupil. Two types have been described: a recessive, syndromic (Pierson syndrome OMIM 609049) and a dominant, isolated form (MCOR syndrome OMIM 156600). Fares-Taie and colleagues described inherited microdeletions in chromosome band 13q32.

Borate transporter SLC4A11 mutations cause both Harboyan syndrome and non-syndromic corneal endothelial dystrophy.

Harboyan syndrome, or corneal dystrophy and perceptive deafness (CDPD), consists of congenital corneal endothelial dystrophy and progressive perceptive deafness, and is transmitted as an autosomal recessive trait. CDPD and autosomal recessive, non-syndromic congenital hereditary endothelial corneal dystrophy (CHED2) both map at overlapping loci at 20p13, and mutations of SLC4A11 were reported recently in CHED2. A genotype study on six families with CDPD and on one family with either CHED or CDPD, from various ethnic backgrounds (in the seventh family, hearing loss could not be assessed because of the proband's young age), is reported here.