ABSTRACT
The timing and sequence of events that follow specific genetic mutations that cause corneal diseases vary considerably. Some become manifest during early corneal development as developmental anomalies; others do not become apparent until later in life. Some genetically determined disorders are restricted to the cornea: others also affect other parts of the eye or are components of a systemic disorder. Some corneal diseases have a simple Mendelian inheritance, others, probably involve more than one gene or an interaction between genetic and environmental factors (see Chapter 31). The affect on vision and the disability created varies with the disorder. During the past decade mutations in more than 38 genes that affect the cornea have been identified and the genes for other corneal disorders have been mapped to specific chromosomal loci (Table 1).
