OMIM ID:
Cataracts, Congenital, Autosomal Recessive 3
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
This type of congenital cataract has been reported in two unrelated Pakistani families. The phenotype was dissimilar in the two families. In one, only posterior subcapsular opacification was present. In the other the cataract was membranous and accompanied by a corneal opacity, microcornea, and nystagmus. Nothing is known about the course of the opacification.
Systemic Features
No systemic disease is apparently present.
Genetics
Inheritance
Consanguinity was reported for both families. Fine mapping identified a locus at 1p34.3-p32.2 that cosegregates with the lens opacities but the mutation is unknown. This region is distinct from the locus containing the mutation(s) causing Volkmann (115665) and posterior polar (116600) autosomal dominant cataracts.
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.