We define a phenotypically distinct autosomal dominant retinal dystrophy syndrome, ROSAH, with features of retinopathy, optic nerve edema, splenomegaly, anhidrosis, and headache in five unrelated families, and show heterozygous (c.710C>T, [p.Thr237Met]) ALPK1 as the causative variant in all cases. This evidence concerns the gene ALPK1 and Splenomegaly.