PURPOSE: Keratocan is a cornea-specific keratan sulfate proteoglycan found predominantly in the adult vertebrate eye. In human beings, mutations in keratocan (KERA) are associated with autosomal recessive cornea plana (CNA2), which is characterized by a flattened forward convex curvature of the cornea. Here, we report a novel mutation in a case of autosomal recessive bilateral cornea plana presenting with primary angle-closure glaucoma in a 41-year-old woman from Eastern India. METHODS: The KERA gene of the patient and her sons was directly sequenced. RESULTS: Mutational analysis of the KERA revealed 2 novel mutations. The first mutation was a 3 base-pair deletion (c.371_373delTCT), leading to the loss of a highly conserved amino acid (p.Phe125del). The second mutation was a base substitution resulting in a silent mutation (c.69G>A). One of her 2 sons carried the homozygous substitution (c.69G>A), whereas the other son was heterozygous (c.69G>R). CONCLUSIONS: The mutation that we report here leads to the deletion of a conserved amino acid (p.Phe125del) from the third LRR motif of the keratocan protein, which might lead to an abnormal tertiary structure of the protein, thereby leading to the disease.
PURPOSE: Keratocan is a cornea-specific keratan sulfate proteoglycan found predominantly in the adult vertebrate eye. In human beings, mutations in keratocan (KERA) are associated with autosomal recessive cornea plana (CNA2), which is characterized by a flattened forward convex curvature of the cornea. Here, we report a novel mutation in a case of autosomal recessive bilateral cornea plana presenting with primary angle-closure glaucoma in a 41-year-old woman from Eastern India. METHODS: The KERA gene of the patient and her sons was directly sequenced. RESULTS: Mutational analysis of the KERA revealed 2 novel mutations. The first mutation was a 3 base-pair deletion (c.371_373delTCT), leading to the loss of a highly conserved amino acid (p.Phe125del). The second mutation was a base substitution resulting in a silent mutation (c.69G>A). One of her 2 sons carried the homozygous substitution (c.69G>A), whereas the other son was heterozygous (c.69G>R). CONCLUSIONS: The mutation that we report here leads to the deletion of a conserved amino acid (p.Phe125del) from the third LRR motif of the keratocan protein, which might lead to an abnormal tertiary structure of the protein, thereby leading to the disease.
Authors: Aleck E Cervantes; Katherine M Gee; Martha F Whiting; Ricardo F Frausto; Anthony J Aldave Journal: Ophthalmic Genet Date: 2018-04-19 Impact factor: 1.803
Authors: Daniel Jackson; Samantha Malka; Philippa Harding; Juliana Palma; Hannah Dunbar; Mariya Moosajee Journal: Am J Med Genet C Semin Med Genet Date: 2020-08-23 Impact factor: 3.908