Online Mendelian Inheritance in Man (OMIM) (original) (raw)

# 611638

MICROPHTHALMIA/COLOBOMA 5; MCOPCB5

ORPHA: 98938;

Phenotype-Gene Relationships

TEXT

A number sign (#) is used with this entry because of evidence that microphthalmia/coloboma-5 (MCOPCB5) is caused by heterozygous mutation in the Sonic hedgehog gene (SHH; 600725) on chromosome 7q36.

For a discussion of genetic heterogeneity of isolated colobomatous microphthalmia, see MCOPCB1 (300345).

Clinical Features

Schimmenti et al. (2003) examined an 8-month-old boy with bilateral microphthalmia, bilateral inferonasal coloboma of the iris, a right-sided chorioretinal coloboma involving the entire optic disc and extending into the fovea, and a left-sided uveoretinal coloboma sparing the optic disc and macular area. The boy had no stigmata of holoprosencephaly or other anomalies or malformations, and on follow-up at age 11 years, he was an honors student with no serious medical illnesses. The mother of the proband was initially believed to be phenotypically normal, but thorough ophthalmic examination revealed a subtle right-sided inferonasal iris defect and a minimal uveoretinal coloboma, with a normal left eye. She had no findings suggestive of a syndromic malformation. Examination of the father, a brother, and other family members showed no ocular or other physical defects.

Molecular Genetics

In a boy with bilateral colobomatous microphthalmia, Schimmenti et al. (2003) identified heterozygosity for a 24-bp deletion in the SHH gene (600725.0016). His mother, who had unilateral iris and uveoretinal coloboma, and 3 unaffected family members carried the same deletion. The authors noted that incomplete expression of SHH mutations had also been observed in several holoprosencephaly pedigrees (see Nanni et al., 1999).

REFERENCES

1. Nanni, L., Ming, J. E., Bocian, M., Steinhaus, K., Bianchi, D. W., de Die-Smulders, C., Giannotti, A., Imaizumi, K., Jones, K. L., Del Campo, M., Martin, R. A., Meinecke, P., Pierpont, M. E. M., Robin, N. H., Young, I. D., Roessler, E., Muenke, M.The mutational spectrum of the Sonic hedgehog gene in holoprosencephaly: SHH mutations cause a significant proportion of autosomal dominant holoprosencephaly. Hum. Molec. Genet. 8: 2479-2488, 1999. [PubMed: 10556296] [Full Text: https://doi.org/10.1093/hmg/8.13.2479\]
2. Schimmenti, L. A., de la Cruz, J., Lewis, R. A., Karkera, J. D., Manligas, G. S., Roessler, E., Muenke, M.Novel mutation in Sonic hedgehog in non-syndromic colobomatous microphthalmia. Am. J. Med. Genet. 116A: 215-221, 2003. [PubMed: 12503095] [Full Text: https://doi.org/10.1002/ajmg.a.10884\]

Creation Date:

Marla J. F. O'Neill : 11/29/2007

Edit History:

alopez : 02/21/2024
carol : 02/26/2014
mcolton : 2/26/2014
joanna : 3/2/2010
terry : 10/8/2008
carol : 11/29/2007