Analphoid de novo marker chromosome inv dup(3)(q28qter) with neocentromere in a dysmorphic and developmentally retarded girl

In the March 1999 issue of the journal, Portnoi et al 1 reported on a patient with a marker chromosome with neocentromere which originated from distal 3q. Here we describe a further example of this type of marker chromosome from distal 3q, which is substantially smaller. The marker was ascertained during cytogenetic diagnosis of a 5 year old girl with marked developmental delay and mild facial dysmorphism. Body measurements were birth length 49 cm, birth weight 2965 g, and OFC 34 cm. At the age of 8.5 years, height was 131 cm, and weight was 37 kg (>97th centile) as a result of hyperphagia which developed two years ago. Dysmorphic signs included hypognathia, broad and flat nasal root, and abnormally shaped alae nasi (fig 1). The median upper lids showed atypical epicanthus. Furthermore, the girl showed slight hirsutism and a bilateral ichthyosiform hyperkeratosis of the palms and soles. On clinical investigation at the age of 5 years our proband presented with slight muscular hypotonia and hyporeflexia. Perceptive skills and visuomotor coordination were retarded corresponding to a developmetal age of 3-3.5 years. At the age of 8.5 years the girl attends a special school for mentally handicapped children. She cannot speak properly, searching for words, can recognise only between 10 and 15 letters, and is still not able to write. Figure 1 The proband aged 4 years. ### Key points