ABSTRACT
We describe a family in which non-syndromic mental retardation (MR) and an apparently balanced reciprocal translocation, t(1;17)(p36. 3;p11.2) segregates in eight individuals over three generations. Four children showed psychomotor developmental delay, reduced muscle tone, poor coordination, and learning difficulties. The affected adults had a varying range of behavioral problems and difficulties in social adjustment but no abnormal neurological signs. Most of them were functioning at the borderline learning difficulty level in intellectual abilities with additional specific difficulties in reading in two individuals. The Smith-Magenis and 1p36.3 deletion syndromes were excluded. We propose that this reciprocal translocation has disrupted an autosomal gene with an important function in cognitive development, and this family represents a unique resource for the molecular genetic study on non-syndromic MR.
Subject(s)
Chromosomes, Human, Pair 17 , Chromosomes, Human, Pair 1 , Intellectual Disability/genetics , Translocation, Genetic , Adolescent , Adult , Aged , Child , Child, Preschool , Family Health , Female , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Male , Middle Aged , PedigreeABSTRACT
A child with the Tel Hashomer camptodactyly syndrome is reported. Although muscle weakness and hypoplasia are reported features of this syndrome, further investigation of muscle function has not previously been carried out. We report a raised creatine kinase and an abnormal electromyogram and muscle biopsy in this syndrome. The histology of the muscle biopsy shows a wide range fibre diameter in type 1 and type 2 fibres with a relative deficiency of type 2b fibres. It is suggested that this condition may be primarily a myopathy.