A novel de novo microdeletion at 17q11.2 adjacent to NF1 gene associated with developmental delay, short stature, microcephaly and dysmorphic features

Abstract

Background: Microdeletions at 17q11.2 often encompass NF1 gene, is the cause for NF1 microdeletion syndrome. Microdeletion at 17q11.2 without the involvement of NF1 gene is rarely reported.

Case presentation: Here we reported a patient carrying a novel de novo deletion at 17q11.2 adjacent to NF1 gene, who presented with developmental delay, short stature, postnatal microcephaly, underweight and dysmorphic features including flat facial profile, dolicocephaly, hypertelorism, short philtrum, flat nasal bridge and posteriorly rotated and low set ears. Chromosomal microarray analysis revealed a 1.69 Mb de novo deletion at 17q11.2 adjacent to NF1 gene, which involves 43 RefSeq genes. We compared this with four overlapping deletions at this interval.

Conclusions: A rare de novo microdeletion at 17q11.2 not involving NF1 gene is associated with developmental delay and dysmorphic features. Seven genes, TAOK1, PHF12, NUFIP2, SLC26A4, SEZ6, GIT1 and TRAF4 are possible candidates for the clinical features of our patient. The delineation of this rare deletion and description of associated clinical phenotypes will help to understand the genotype-phenotype correlation of genomic imbalances at this locus.

Keywords: 17q11.2; Chromosomal microarray; Developmental delay; Microcephaly; Microdeletion; SNP array; Short stature.

Fig. 1

Clinical features of the patients. Note the facial profile, dolicocephaly and low-set posteriorly rotated ear (a); hypertelorism, low nasal bridge and short philtrum (b); short fifth fingers (c and d)

Fig. 2

SNP array profile showing a deletion on 17q11.2 (a), and schematic representation of 27 Mbp to 31Mbp in 17q11.2 region (b). Blue bars represent genes discussed in this paper. Also shown, the extent of the deletions (in red) observed in reported cases are compared with the presented case