has material basis in existence starts during autosomal recessive disease retinitis pigmentosa 108 disease_ontology DOID:0051101 A retinitis pigmentosa that is characterized by onset of symptoms later in life (fourth to fifth decades) and that has_material_basis_in homozygous or compound heterozygous mutation in the SAXO6 gene on chromosome 12q15. Most affected individuals experience photophobia and reduced visual acuity, and funduscopy shows the typical changes of RP, with optic disc pallor, retinal vessel attenuation, and bone-spicule pigmentary changes in the midperiphery. MIM:621637 retinitis pigmentosa autosomal recessive inheritance Middle age onset