Background: Overgrowth syndromes comprise a group of disorders associated with excessive growth and other features such as facial dysmorphism, developmental delay, neurological problems and an increased risk of neoplasia. The genetic basis for many of these conditions is being increasingly elucidated. Here, we report on a 3-year-old boy who was referred for evaluation of generalized overgrowth.
Objective and hypotheses: Our hypotheses is that unclassified overgrowth syndromes may be caused by subtle genomic imbalances.
Method: Array-CGH was performed as the first line investigation, using DNA extracted from the blood and analyzed utilizing an Affymetrix cytoscan 750K array (Genome build: Hg19).
Results: A 3-years-boy is the second child of unrelated healthy parents of normal stature. He was born at term with uneventful. Dysmorphic features included high and prominent forehead, hypertelorism, and small mouth. Other features were noted, including cryptorchidism, retractile testis, and developmental delay. Vigorous appetite was also shown in the patient at 1 year of age. He began to walk unaided at 23 months of age, and could sign one words at 3 years of age. To date, at 3 years, height was 106.1 cm (>97th percentile), weight 26.4 kg (>97th percentile) and head circumference 56 cm (>97th percentile). In order to determine putative chromosomal imbalances, microarray array was performed, resulting in a 2.2 Mb deletion in chromosome region 7q22.1-22.3 covering 2,244,033 bp region. The deletion was starting from 102,877,293 bp extending to 105,121,326 bp which contain involved 9 genes including PMPCB, DNAJC2, PSMC2, SLC26A5, RELN, ORC5, LHFPL3, KMT2E, and SPRK2.
Conclusion: This is the first report on generalized overgrowth syndrome having 7q22.1-7q22.3 microdeletion. We should consider performing array-CGH for the diagnosis of unclassified overgrowth syndromes, because some still it may be caused by subtle genomic imbalances.
10 Sep 2016 - 12 Sep 2016