Myopia 1, X-linked, Nonsyndromal

Background and History: 

Refractive errors, in the absence of other eye disease, for which corrective lenses are prescribed, have been known since antiquity.  It has also been recognized that they are often familial although the transmission pattern does not follow the usual patterns of simple, single gene inheritance.  This condition of simple myopia (nearsightedness) is one of the few exceptions.

Clinical Correlations: 

At least three families have been reported in which only males had marked nearsightedness. The onset was reported to be late in the first decade of life.  No other ocular abnormalities were present and specifically reports do not mention retinal thinning or detachments.

Genetics: 

In reported families only males were highly nearsighted although some females had low-grade myopia.  In these families the inheritance pattern was consistent with X-linked inheritance and an area purported to contain a gene mutation was found to be located on the X-chromosome.

Diagnosis and Prognosis: 

The diagnosis of nearsightedness is usually made late in the first decade of life by ophthalmologists.  The initial evaluation should include a detailed retina examination as myopia is a risk factor for retinal degeneration and detachment.  Moreover, since myopia occurs in many heritable diseases, it is important that a complete general physical examination be done to ensure that no other condition is present.

Additional Information
Inheritance/Pedigree: 
X-linked recessive, carrier mother
X-linked recessive, father affected