VSX1 and keratoconus: Interestingly, the p.(G160V) variant, which results in a different amino acid substitution at the same position, has been observed in cases in two Korean studies.[40, 57] The p.(P247R) variant originally reported in the PPD family[31] and subsequently reported in keratoconus[38, 43, 51] was observed in a single control subject in our study.