What is LCA?

familyInherited retinal diseases (also called inherited retinal dystrophies, or IRDs) are a group of rare eye disorders caused by an inherited gene mutation and can result in vision loss or blindness. They include retinitis pigmentosa, Leber congenital amaurosis, cone-rod dystrophy, juvenile macular degeneration, choroideremia, and many others.

Leber congenital amaurosis (LCA) is a rare inherited retinal disease (IRD) that causes the degeneration of the cone and rod cells in the retina. It is characterized by severe vision loss at birth and results in complete blindness. While some children are born with little or no vision, others may have significant vision loss in the first few years of life, stable vision for a period of time, and then eventually total vision loss. LCA is estimated to occur in about 1 in 33,000 people.

LCA can be difficult to diagnose. LCA has a variety of symptoms and is often confused with other eye diseases. Infants’ eyes look normal, but they may have unusual eye movement, sensitivity to light, deep-set eyes, or a lack of visual responsiveness. Low retinal activity can be tested by electroretinogram (ERG) to help determine if a person has LCA, but eye doctors are often unfamiliar with LCA.

In many cases, diagnosis involves sophisticated clinical tests and genetic testing to identify the associated genetic abnormality that causes LCA. There are nearly 30 genes that are believed to be associated with this rare disease. A mutation in just one of these genes will result in blindness.

There are currently 27 validated LCA genes, according to the Retinal Information Network.

  • LCA1 (GUCY2D)
  • LCA2 (RPE65)
  • LCA3 (SPATA7)
  • LCA4 (AIPL1)
  • LCA5 (LCA5)
  • LCA6 (RPGRIP1)
  • LCA7 (CRX)
  • LCA8 (CRB1)
  • LCA9 (NMNAT1)
  • LCA10 (CEP290)
  • LCA11 (IMPDH1)
  • LCA12 (RD3)
  • LCA13 (RDH12)
  • LCA14 (LRAT)
  • LCA15 (TULP1)
  • LCA16 (KCNJ13)
  • LCA17 (IQCB1)
  • CABP4
  • CCT2
  • CTNNA1
  • CYP4V2
  • CLUAP1
  • DTHD1
  • GDF6
  • IFT140
  • OTX2
  • PRPH2