Retinitis Pigmentosa 59
Retinitis pigmentosa (RP) is a degenerative eye disease resulting from retinal dystrophy, leading to loss of peripheral vision and blindness. RP is a heterogeneous disease, with many different causative genes that result in various subtypes. Many affected patients in the Ashkenazi Jewish population were found to have mutations in the gene DHDDS, which cause retinitis pigmentosa 59. In one study, 12% of RP patients with Ashkenazi Jewish ancestry had DHDDS mutations, whereas mutations in this gene accounted for less than 1% of RP in the general population. The p.K42E mutation accounts for over 97% of reported DHDDS mutations in the Ashkenazi Jewish population. Therefore, testing for this mutation is expected to identify over 95% of mutations in the Ashkenazi Jewish population, where the carrier frequency for this variant has been estimated at 1 in 117.
Full gene sequencing is available for reproductive partners of known mutation carriers. Prenatal diagnosis is also available. Prior to ordering prenatal testing, please contact our laboratory at 212-241-7518 to discuss.
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2. Züchner S, Dallman J, Wen R, Beecham G, Naj A, Farooq A, Kohli MA, Whitehead PL, Hulme W, Konidari I, Edwards YJ, Cai G, Peter I, Seo D, Buxbaum JD, Haines JL, Blanton S, Young J, Alfonso E, Vance JM, Lam BL, Peri?ak-Vance MA. Whole-exome sequencing links a variant in DHDDS to retinitis pigmentosa. Am J Hum Genet. 2011 Feb 1188(2):201-6.
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