The single 4 generation family tree reported is consistent with autosomal dominant inheritance. Several likely loci on chromosomes 1, 5, 8, 11, and 17 have been reported but no candidate gene has been identified.
Other conditions in which small pupils are found are Pierson syndrome (609049) and Warburg micro syndrome (600118) but these are associated with significant systemic abnormalities.
Congenital microcoria (156600) is an autosomal dominant disorder with mild axial myopia and goniodysgenesis resulting from an unidentified mutation on chromosome 13. Glaucoma is a common finding as is some iris hypoplasia. Despite some clinical similarities, this is likely a unique disorder.