Congenital ectodermal dysplasias (EDs) are a group of familial disorders that affect tissues and organs of ectodermal origin to varying degrees. Since the otic capsule is of ectodermal origin, it is not surprising to find sensorineural hearing loss associated with ED. However, we could find only eight such cases in the literature. The present communication reports on two siblings affected with ED associated with sensorineural hearing loss. Results from a battery of hearing tests suggest a degeneration of the hair cells in the organ of Corti. The mode of inheritance in these cases is one of autosomal recessive form.
Abstract We report on a patient with oculo‐dento‐osseous dysplasia and bilateral persistence of the hyaloid system. Autosomal recessive inheritance may be the cause of this patient's condition since she was born to unaffected first‐cousin parents. Ocular findings in the recessive variety of this syndrome seem to be more severe than those in the more common dominant form.
We report on a 4-year-old boy with Knobloch syndrome. He has vitreoretinal degeneration, high myopia, cataract, telecanthus, hypertelorism, and a high-arched palate. He also has a defect of the anterior midline scalp with involvement of the frontal bone as documented by a computed tomography (CT) scan. The brain was normal on CT scan and magnetic resonance imaging. We present a review of the 23 published cases with this syndrome. Our patient illustrates the importance of investigating for underlying ocular and central nervous system pathology whenever midline scalp defects are present.
Abstract A Vietnamese‐Czechoslovak type 1 Gaucher disease patient with mild hematological complications was found to have approximately 20% of the normal level of fibroblast glucocerebrosidase activity. Using primers that recognize exon 9 sequences of the glucocerebrosidase structural gene absent in the pseudogene, genomic DNA sequences flanking exons 9 and 10 of the glucocerebrosidase structural gene were amplified by the polymerase chain reaction. Allele‐specific oligonucleotide hybridization to amplified genomic DNA sequence of exons 9 and 10 showed an A→G transition in exon 9 that resulted in the 370 Ser→ 370 Asp substitution in one of the alleles. In the other allele, a T→C transition in exon 10 resulted in the 444 Leu→ 444 Pro substitution, creating a NciI cleavage site. The heterozygote status of the patient's parents was confirmed biochemically by the detection of intermediate levels (42–55% of normal) of fibroblast glucocerebrosidase activity. Allele‐specific oligonucleotide hybridization to amplified parental genomic DNA showed that the exon 9 mutation was present in the Czechoslovak father, whereas the exon 10 mutation was inherited from the patient's Vietnamese mother. This is the first report of the exon 10 mutation in a person of Vietnamese origin.
Two siblings, a girl and a boy, of consanguineous parents were thought to have the Rubinstein-Taybi syndrome. They have mental, motor, and growth retardation, microcephaly, odd but characteristic facial features, ocular abnormalities, and high arched palate. The boy has cryptorchidism. Broad thumbs and first toes described in all previously reported cases are absent clinically and are questionable radiologically. Findings of broad thumbs and first toes should not be considered essential for diagnosis. Cause of the syndrome is unknown. Because it occurs in siblings of closely consanguineous parents, genetic cause is suggested. Autosomal recessive inheritance pattern is favored. Conventional light microscopy and high resolution light microscopy of muscle revealed denervation atrophy. Electron microscopy revealed changes in glycogen, sarcoplasmic reticulum profile, contractile apparatus, and intramuscular nerves. These are not yet reported in this syndrome.
