OMIM ID:
Microphthalmia, Syndromic 10
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
Microphthalmia seems to be a common feature. The globes have anterior-posterior dimensions of 5-8 mm. No internal ocular structures can be visualized and individuals are likely blind. The corneal diameters in two patients were measured at 3-4 mm. The optic nerves have been described as ‘slender’ on brain imaging.
Systemic Features
Head circumference ranges from the 10th to the 25th percentile at birth Psychomotor development has been described as normal during the first 6 to 8 months but is followed by rapid deterioration in performance with spasticity, vomiting and continuous crying. An MRI on one 3 day old patient was reported as normal while at 15 months of age there was atrophy of the vermis and corpus callosum and at 8 years of age the atrophy of these structures was even more extensive. Similar atrophy patterns were seen in the two other patients and eventually all cerebral while matter is lost and there is atrophy of the brainstem as well.
Genetics
Inheritance
Three children from 3 consanguineous Pakistani families have been reported but no locus or mutation has been identified.
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.