The BEST1 gene (OMIM 607854, formerly named VMD2: OMIM 153700), which contains 11 exons and is located on chromosome 11q12-13, has been identified as the disease-causing gene for a variety of diseases called bestrophinopathies, such as BVMD, ARB, retinitis pigmentosa, and autosomal dominant vitreoretinochoroidopathy (ADVIRC) [13, 14]. Here, BEST1 is linked to MRCS syndrome.