Purpose: To perform a detailed morphologic and functional evaluation of Best m acular dystrophy (BMD) associated with mutations in the VMD2 gene. Design: Retro spective study. Participants: The records of 16 patients with BMD and heterozygo us VMD2 mutations (group 1) and 5 patients with Best-like lesions with no detec table disease-associated alterations in the VMD2 gene (group 2) were evaluated retrospectively. Methods: The data were reviewed regarding visual acuity (VA), c olor vision, perimetry, autofluorescence of the retinal pigment epithelium (RPE) , fluorescein angiography, electro-oculography (EOG), and full-field electrore tinography (ERG) and multifocal ERG (mfERG). Main Outcome Measures: VMD2 mutatio ns, age at onset of BMD, RPE auto-fluores- cence, EOG, ERG, and mfERG. Results: The mean age of the patients in group 1 w as 47.1 years (range, 16.7-86.5), and age at onset varied between 5 and 58 year s (median, 42.0). Visual acuity ranged between 20/16 and 20/400 (median, 20/40). No association existed between the specific nature of theVMD2 mutation and dise ase onset or expressivity. Retinal pigment epithelium autofluorescence was incre ased corresponding to ophthalmoscopically visible yellow material, whereas it wa s decreased in the atrophic stage of BMD. Electro-oculography light rise was re duced in 18 of 19 eyes. Electroretinography amplitudes were normal in 3 patients and reduced in 6 patients. Multifocal ERG revealed in 10 of 20 eyes a central a mplitude reduction and in 7 eyes a generalized one. There were no marked differe nces in clinical and functional findings between the patients in groups 1 and 2, except that the mean age of the patients in group 2 was higher (64.0 years [ra n ge, 45.7-80.6]) and the median VA lower (20/50 [range, 20/32-20/320]). Conc lus ions: The onset of BMDis highly variable and occurred in the majority of patient s after the second decade of life. Bestlike lesions may develop in older patient s without associated VMD2 mutations. Those manifestations may be related to a sp ecific form of age-related macular degeneration. Purpose: To perform a detailed morphologic and functional evaluation of Best m acular dystrophy (BMD) associated with mutations in the VMD2 gene. Design: Retro spective study. Participants: The records of 16 patients with BMD and heterozygo us VMD2 mutations (group 1) and 5 patients with Best-like lesions with no detec table disease-associated alterations in the VMD2 gene (group 2) were evaluated retrospectively. Methods: The data were reviewed regarding visual acuity (VA), olor vision, perimetry, autofluorescence of the retinal pigment epithelium (RPE), fluorescein angiography, electro-oculography (EOG), and full-field electroretinography (ERG) and multifocal ERG (mfERG). Main Outcome Measures: VMD2 mutatio ns, age at onset of BMD, RPE auto- Results: The mean age of the patients in group 1 w as 47.1 years (range, 16.7-86.5), and age at the onset varied between 5 and 58 years (median, 42.0) Visual acuity ranged between 20/16 and 20/400 (median, 20 / 40). No association existed between the specific nature of theVMD2 mutation and disesession onset or expressivity. Retinal pigment epithelium autofluorescence was increased corresponding to ophthalmoscopically visible yellow material, but it wa s decreased in the atrophic stage of BMD. Electro-oculography light rise was re duced in 18 of 19 eyes. Electroretinography amplitudes were normal in 3 patients and reduced in 6 patients. Multifocal ERG revealed in 10 of 20 eyes a central a mplitude reduction and in 7 eyes a generalized one. There were no marked differe nces in clinical and functional findings between the patients in groups 1 and 2, except that the mean age of the patients in group 2 was higher (64.0 years [ra ge, 45.7-80.6]) and the median VA lower (20/50 [ range, 20 / 32-20 / 320]). Conc lus ions: The onset of BMDis highly variable and occurred in the majority of patient s after the second decade of life. Bestlike lesions may develop in older patient s without associated VMD2 mmutations. Those manifestations may be related to a specific form of age-related macular degeneration.