De novo duplication (19)(q13.1q13.3); second case with a mild phenotype
Duplication of chromosome 19q is an uncommon cytogenetic finding. Most cases have been reported as the result of an unbalanced translocation. Of those cases that are the result of a pure duplication, most have significant physical and developmental problems with a resultant poor prognosis.
The case presented here has relatively mild features. She was born following a normal pregnancy weighing 4.2kg at term. There were no early concerns about her growth or development. She had been assessed by an ophthalmologist because of a family history of retinitis pigmentosa. Her eyes were normal. At 8 months she had physiotherapy as she had low muscle tone and was not rolling or sitting. Investigations carried out at this time showed a de novo duplication, 46,XX,dup(19)(q13.1q13.3).ish dup(19)(q13.1q13.3)(wcp19+,D19S238E+). At 11 months, she had remained relatively tall for her age with a relatively large head. She had mild plagiocephaly and wide spaced eyes. She had 2 grooves in her right ear lobe and bilateral preauricular pits. A cerebral CT scan was normal. She was sitting and rolling and had 2-3 words. She was about 2 months behind in most areas of development.
This is only the second case with a duplication of 19q with a relatively mild phenotype. The features will be discussed in more detail.