OMIM ID:
Myopia, AR, with Cataracts and Vitreoretinal Degeneration
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
Axial myopia and poor vision are noted during childhood. Most individuals have refractive errors in the range of-5 to -18 diopters with a mean spherical equivalent of -11.3 diopters. The axial length ranges from 25.1 and 30.5 mm. Peripheral vitreoretinal degeneration and cataracts are usually present after the onset of myopia. Lenticular opacities may necessitate cataract surgery in 11 of the 13 myopic patients in one kindred, usually by the second decade of life. Lens instability or frank subluxation was noted in 8 patients. At least five eyes suffered retinal detachments secondary to retinal dialyses and blindness of at least one eye occurred in 23% of patients.
Systemic Features
Deafness was reported in a single patient.
Genetics
Inheritance
This condition results from homozygous mutations in the gene LEPREL1 (3q28) encoding prolyl 3-hydroxylase. It was identified in a large consanguineous Israeli Bedouin kindred containing seven affected males and 6 affected females.
Pedigree
Autosomal recessive
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.