Khan et al. (2008) performed FOXC1 mutational screening on an infant and her consanguineous parents. Both the infant and her mother were suffering from congenital glaucoma and aniridia. A heterozygous T>A point mutation was identified in the infant and her mother, but not the father, resulting in an amino acid substitution at a highly conserved methionine with lysine at position 161 (p.M161K). This mutation was not found in 100 Saudi controls. In a subsequent study to determine the genetic and genomic alterations underlying classic aniridia in Saudi Arabia, Khan et al. (2011) conducted a prospective study of consecutive patients referred to a pediatric ophthalmologist (2005-2009). All 12 probands (4 months-25 years of age; four boys and eight girls) were products of consanguineous unions except for three, one of which was endogamous. Heterozygous PAX6 mutations (including two novel mutations) were detectable in all but two cases, both of which were sporadic. In one of these two cases, the phenotype segregated with homozygosity for a previously-reported pathogenic missense FOXC1 variant (p.P297S) when homozygosity for chromosome 11q24.2 deletion (chr11:125,001,547-125,215,177 [rs114259885; rs112291840]) was also present. In the other, no genetic or genomic abnormalities were found. In year 2013, Khan et al. documented an unusual pattern of acquired peripheral circumferential iris degeneration in two unrelated children with otherwise-controlled congenital glaucoma. In one family, genetic testing revealed a novel heterozygous FOXC1 deletion (p.Tyr81_Pro95del).