aldred syndrome aldred syndrome aldred syndrome is an x-linked recessive genetic disorder. it is mainly characterized by a form of intellectual disability and retinitis pigmentosa. the syndrome was first described by geneticist micheala aldred in 1994. aldred syndromeother namesretinitis pigmentosa and intellectual disability due to xp11.3 microdeletion cause aldred syndrome is caused by a deletion on the p11.3 area of the x-chromosome.