Neuropediatrics 2010; 41 - P1310
DOI: 10.1055/s-0030-1265556

De novo deletion 17p13.1 and duplication 17p11.2 in a seven months-old male infant with the clinical features of Potocki-Lupski syndrome

M Laufs 1, R König 2, S Geb 1, S Vlaho 1, M Kieslich 1
  • 1Department of Pediatrics, Goethe-University, Frankfurt/M.
  • 2Institute of Human Genetics, Goethe-University, Frankfurt/M.

Aims: Potocki-Lupski syndrome (PTLS [OMIM 610883]) is a contiguous gene syndrome caused by duplication of 17p11.2. PTLS overlaps with Smith-Magenis syndrome (SMS [OMIM 182290]), which is associated with deletion 17p11.2 and is characterised by muscular hypotonia, poor feeding, failure to thrive in infancy, developmental delay, vision and hearing impairment, autism, scoliosis, genitourinary and cardiovascular anomalies.

Case: Born at term via naturalis after an uncomplicated pregnancy (weight 3170g, length 56.5cm, head circumference 36.8cm, APGAR 5/6) the patient initially required short term assisted ventilation and showed excessive muscular hypotonia, reduced spontaneous motor activity, decreased deep tendon reflexes and impaired coordination of suck-swallow-respiration. He required tube feeding for 6 weeks. The cerebral MRI at the age of 3 months showed frontal pachygyria, dilatation of the inner CSF spaces and a hypoplastic corpus callosum. At the age of seven months motor developmental delay became evident.

The following stigmata were observed: scoliosis and thoracic gibbus, dolichocephaly, narrow palpebral fissures, strabismus convergens, myopia, flat nasal bridge and root, anteverted nares, microstomia, high-arched palate, low-set posteriorly rotated ears, hearing impairment, inverted widely spaced nipples, overlapping long fingers and toes (dig. II/III), and hypoplastic scrotum.

Methods: Conventional chromosomal analysis (GPG banding).

Array CGH of genomic DNA with the Microarray Kit 244A.

Results: Conventional chromosomal analysis: structural abnormality of chromosome 17.

Array-CGH: deletion in region 17p13.2-p13.1 (base-pair position 5.229.221–7.784.656), duplication in region 17p11.2 (region 1: base-pair position 17.486.315–18.215.798; region 2: base-pair position 18.615.732–19.486.960).

Conclusion: In this case, a complex malformation and retardation syndrome with emphasis on muscular hypotonia and developmental delay is associated with both a deletion and a duplication of a part of the short arm of chromosome 17 detailed by Array-CGH. Because of the large number of affected genes, a specific genotype-phenotype correlation is not possible. However the patient's PTLS-like symptoms correspond well to the duplicated region 17p11.2 completely covering the PTLS region.