Sir,
The report from Iran on “VSX1 and SOD1 mutation screening in patients with keratoconus” is interesting.[1] Nejabat et al concluded that “it will be necessary to investigate other chromosomal loci for potential causal mutations of keratoconus using next generation sequencing (NGS) methods in our population.[1]” Nejabat et al observed that “Mutations in VSX1 and SOD1 genes associated with keratoconus were not identified” in their patients.[1] In fact, the negative observation might be because of the small sample size used for detecting focused genetic abnormalities. Other possible genetic polymorphisms or mutations[2,3] associated with keratoconus were not studied by Nejabat et al.[1] In addition, epigenetic factors can also contribute significantly to keratoconus pathogenesis.[4] Finally, there is ambiguity regarding the details of the quality control of the laboratory tests. A discussion on laboratory errors or false positivity due to analytical problems should be included.
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Conflicts of Interest
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REFERENCES
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