OMIM ID:
Lacrimal Puncta Agenesis
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
Nasolacrimal duct obstruction may occur in 20% of infants. The blockage is usually located at the Valve of Hasner in the distal intranasal segment of the nasolacrimal drainage system. In the absence of other anatomic anomalies, the obstruction often spontaneously clears by one year of age. Recurrent conjunctivitis and epiphora are frequent occurrences. A dacryocystocele may develop and in the lacrimal sac area and purulent material can often be expressed by applying mild pressure.
However, the literature contains scattered references to rare familial cases with recurrent dacryocystitis in which a dacryocystocele and lacrimal puncta agenesis are present.
Systemic Features
Facial cellulitis and respiratory distress may be associated.
Genetics
Inheritance
Homozygous mutations in the IGSF3 gene (1p13) have been reported in multiple male offspring of a consanguineous couple. The parents and an unaffected brother were heterozygous for the mutation.
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.