OMIM ID:
Basel-Vanagaite-Smirin-Yosef Syndrome
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
The eyes appear abnormally far apart. Ptosis, microcornea, congenital cataracts, sparse eyebrows, and strabismus are usually present. Epicanthal folds are often seen.
Systemic Features
Psychomotor development is severely delayed and with delay or absence of milestones. DTRs are often hyperactive but some infants are described as hypotonic. Some individuals have seizures. There may be a nevus flammeus simplex lesion on the forehead and body hair is sparse. Cleft palate, cardiac septal defects, hypospadius, thin corpus callosum and cerebral ventricular dilation have been observed. The upper lip may have a tented morphology with everted lower lip vermilion. A short philtrum is common.
Genetics
Inheritance
A homozygous missense mutation in the MED25 gene (19q13.33) has been reported and the transmission pattern is consistent with autosomal recessive inheritance.
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.