Macular Dystrophy, Patterned 2

Clinical Characteristics
Ocular Features: 

Abnormal pigmentation of yellow, white, or black color accumulates in the central area of the macula.  The deposition of pigment appears in the retinal pigment epithelium (RPE) level in a pattern more or less resembling the wings of a butterfly.  The peripheral retina has diffuse pigment mottling.  Drusen-like structures may be seen at the peripheral borders of the macular pigmentation.  Visual fields are normal usually but there may be some decrease in central sensitivity.

However, this is a generalized retinal disorder as revealed by the abnormal mass response (decreased light/dark ratio) of the electrooculogram (EOG).   Patients may not have visual symptoms until their late 20s or early 30s even though the pigmentation may be evident in the second decade.  Color vision, dark adaptation and the ERG are normal.  Younger patients may have normal vision.

Systemic Features: 

No systemic associations have been reported.

Genetics

This condition results from heterozygous mutations in the CTNNA1 gene (5q31).  For a similar disorder see Macular Dystrophy, Patterned 1 (169150).

As many as 25% of patients with myotonic dystrophy 1 (160900) and myotonic dystrophy 2 (602668) have a patterned pigmentary maculopathy.

Treatment
Treatment Options: 

There is no known treatment.

References
Article Title: 

Mutations in CTNNA1 cause butterfly-shaped pigment dystrophy and perturbed retinal pigment epithelium integrity

Saksens NT, Krebs MP, Schoenmaker-Koller FE, Hicks W, Yu M, Shi L, Rowe L, Collin GB, Charette JR, Letteboer SJ, Neveling K, van Moorsel TW, Abu-Ltaif S, DeBaere E, Walraedt S, Banfi S, Simonelli F, Cremers FP, Boon CJ, Roepman R, Leroy BP, Peachey NS, Hoyng CB, Nishina PM, den Hollander AI. Mutations in CTNNA1 cause butterfly-shaped pigment dystrophy and perturbed retinal pigment epithelium integrity. Nat Genet. 2016 Feb;48(2):144-51.

PubMed ID: 
26691986

References

Saksens NT, Krebs MP, Schoenmaker-Koller FE, Hicks W, Yu M, Shi L, Rowe L, Collin GB, Charette JR, Letteboer SJ, Neveling K, van Moorsel TW, Abu-Ltaif S, DeBaere E, Walraedt S, Banfi S, Simonelli F, Cremers FP, Boon CJ, Roepman R, Leroy BP, Peachey NS, Hoyng CB, Nishina PM, den Hollander AI. Mutations in CTNNA1 cause butterfly-shaped pigment dystrophy and perturbed retinal pigment epithelium integrity. Nat Genet. 2016 Feb;48(2):144-51.

PubMedID: 26691986

den Hollander AI, van Lith-Verhoeven JJ, Kersten FF, Heister JG, de Kovel CG, Deutman AF, Hoyng CB, Cremers FP. Identification of novel locus for autosomal dominant butterfly shaped macular dystrophy on 5q21.2-q33.2. J Med Genet. 2004 Sep;41(9):699-702.

PubMedID: 15342701

Deutman AF, van Blommestein JD, Henkes HE, Waardenburg PJ, Solleveld-van Driest E. Butterfly-shaped pigment dystrophy of the fovea. Arch Ophthalmol. 1970 May;83(5):558-69.