- Heterozygous mutations of OTX2 cause severe ocular malformations. Ragge, N.K., Brown, A.G., Poloschek, C.M., Lorenz, B., Henderson, R.A., Clarke, M.P., Russell-Eggitt, I., Fielder, A., Gerrelli, D., Martinez-Barbera, J.P., Ruddle, P., Hurst, J., Collin, J.R., Salt, A., Cooper, S.T., Thompson, P.J., Sisodiya, S.M., Williamson, K.A., Fitzpatrick, D.R., van Heyningen, V., Hanson, I.M. Am. J. Hum. Genet. (2005)