North Carolina macular dystrophy is a rare disease of the retina assumed to be caused by a gene mutation on chromosome 6. It is named after the geographic location in which the disorder was found in a large family in 1971.
North Carolina macular dystrophy primarily affects the macula which is a special area of the retina with the highest concentration of rods and that we use for our best vision. The macula is located in the central portion of the retina which we use when focusing directly on visual targets (such as printed material). Therefore, any disease which interferes with normal functioning of this portion of the retina will lead to loss of good, sharp vision that we all depend upon for much of our daily activities. This disease is only one of many forms of macular degeneration. Some, such as North Carolina macular dystrophy, are inherited; others are related to aging, trauma, and even other retinal disorders.
North Carolina macular dystrophy is assumed to be caused by an unknown genetic change that is passed from parent to child. The genetic change can result in clinical disease when inherited in a single dose (we all have two copies of our genes, receiving one from each of our parents). The resulting vertical pattern is called 'autosomal dominant'. In general, half (50%) of the children born to someone carrying the North Carolina macular dystrophy mutation will inherit the defect. Most that inherit the genetic change develop changes in the eye, but not all develop symptoms. The severity of disease among parents is not correlated with the nature of clinical disease in their offspring.
Macular disease, including North Carolina macular dystrophy, can usually be diagnosed by your ophthalmologist by examination of the retina. The vison is very variable, ranging from normal to very poor vision. In most cases the vision is stable, but it can get worse in a few individuals. North Carolina macular dystrophy does not cause any clinical problems outside of the eye. No treatment is currently available for the retinal disease nor is gene therapy available.