ABSTRACT
Knobloch syndrome is a rare genetic disorder characterized by high myopia, vitreoretinal degeneration with retinal detachment and occipital cephalocele. The inheritance has been described as autosomal recessive (AR) but in addition to the original report with 5 affected patients [Knobloch and Layer, 1971] only one other family with 2 affected sibs has been described [Czeizel et al., 1992]. We have studied a large consanguineous kindred in which there are 12 patients with severe ocular alterations associated with a congenital occipital encephalocele, compatible with the diagnosis of Knobloch syndrome. CT scan and MRI performed in one of the patients, allowed a better understanding of the cranial and ocular alterations in this syndrome. The pattern of occurrence in this highly inbred family clearly confirms autosomal recessive inheritance of Knobloch syndrome.
Subject(s)
Encephalocele/genetics , Genes, Recessive , Myopia/genetics , Occipital Bone/abnormalities , Retinal Degeneration/genetics , Adolescent , Adult , Brazil , Consanguinity , Dura Mater/abnormalities , Female , Humans , Male , Pedigree , SyndromeABSTRACT
The present report describes a Brazilian Negro sibship with six males affected by a presumptive new variant of Norrie's disease, an X-linked congenital oculo-acoustical-cerebral degeneration. In addition to the typical stigmata of the disease, all the patients were microcephalic and two of them had cryptorchidism. Possible non-genetic aetiology was investigated with negative results. Xg blood group studies were informative and the lod scores are given, together with those for two previously reported families with Norrie's disease.
