Earlier AMD Onset With Rare Genetic Variants
Patients carrying rare genetic variants have higher prevalence of a positive family history
MONDAY, Jan. 18, 2016 (HealthDay News) -- Patients with age-related macular degeneration (AMD) carrying rare variants have earlier age at symptom onset and a higher prevalence of positive family history than noncarriers, according to a study published online Jan. 14 in JAMA Ophthalmology.
Nicole T.M. Saksens, M.D., from the Radboud University Medical Center in Nijmegen, Netherlands, and colleagues determined the contribution of rare CFH Arg1210Cys, CFI Gly119Arg, C9 Pro167Ser, and C3 Lys155Gln variants in AMD development in a retrospective case-control study. Data were included for 114 affected and 60 unaffected members of 22 multiplex families with AMD; 1,589 unrelated patients with AMD; and 1,386 unrelated controls.
The researchers found that the presence of CFI Gly119Arg, C9 Pro167Ser, and C3 Lys155Gln variants was confirmed in 18 individuals from five families, but did not completely segregate with disease. Compared with noncarriers from the case-control cohort, the 91 affected carriers of these variants were younger at symptom onset (P = 0.01) and more often reported a positive family history (P = 0.008). Patients with advanced atrophic AMD more frequently carried these rare variants than patients with neovascular AMD (11.8 versus 4.8 percent; P = 0.04).
"These results suggest that genetic tests for AMD might be designed to detect common and rare genetic variants, especially in families, because rare variants contribute to the age at onset and progression of the disease," the authors write.