Pediatricians’ awareness about malformation syndromes can help in their timely diagnosis. Williams syndrome is a microdeletion syndrome associated with characteristic facial features and behavioral phenotype. Diagnosis can be confirmed by fluorescence-in-situ hybridization or multiplex ligation probe amplification. Correct diagnosis can help in diagnosing hypercalcemia and cardiac defects, and providing genetic counseling to the family.

Keywords: FISH, Microdeletion, Williams syndrome.

Williams syndrome (OMIM 194050) is caused by hemizygous microdeletion on chromosome 7; the estimated prevalence varies from 1: 20000 to 1:50000 live births. It is characterized by cardiovascular disease, distinctive facies and personality, mild intellectual disability, unique personality, and connective tissue growth and endocrine abnormalities. The aim of this communication is to describe the typical facial and other diagnostic features of Williams syndrome.

The data about the facial and other phenotypic features of 11 patients (8 boys) of Williams syndrome diagnosed at our center from 2007 to 2012 were collected. The diagnosis was confirmed by Fluorescence-in-situ- hybridization (FISH) or Multiple Ligation Probe Amplification (MLPA).

The mean age was 8 years. The presenting complaints were developmental delay and/or intellectual disability (in 6 children) or hyperactive behaviour (in 2 children). Fig. 1 shows facial features of 9 children with Williams syndrome. Malar hypoplasia, thick lower lip and bulbous nasal tip were present in 10 cases; periorbital fullness and long philtrum were seen in 8 cases. Seven patients had bi-temporal narrowing and full cheeks, while 6 had short nose and wide mouth. Prominent ear lobes were seen in 5 patients. Epicanthal folds, small jaw, malocclusion of teeth and widely spaced teeth were seen in 3 children. The cardiac anomalies (aortic stenosis, pulmonary stenosis, ventricular septal defect and mitral valve prolapse) were present in 5 out of 9 children in whom echocardiography was done. Four patients had short stature and six had microcephaly.

Fig 1: Facial features of Williams syndrome.

Jurado, et al. [1] suggested that postnatal growth deficiency may be associated with deletion of maternal copy of chromosome 7. One of our patients presented at 3.5 months of age with cholestatic jaundice, paucity of bile ducts and facial dysmorphism. The diagnosis of Williams syndrome was made at 1 year when developmental delay and characteristic facial features became obvious.

There was no infant that had hypercalcemia in our case series. The photographs in this series are expected to give visual impression of the facial features that can help in diagnosis by gestalt.

Acknowledgement: Indian Council for Medical Research.

1. Pérez Jurado LA, Peoples R, Kaplan P, Hamel BC, Francke U. Molecular definition of the chromosome 7 deletion in Williams syndrome and parent-of-origin effects on growth. Am J Hum Genet. 1996;59:781-92.

2. Patil SJ, Madhusudhan BG, Shah S, Suresh PV. Facial phenotype at different ages and cardiovascular malformations in children with Williams-Beuren syndrome: a study from India. Am J Med Genet A. 2012;158A:1729-34.

3. Ferrero GB, Biamino E, Sorasio L, 　Banaudi E,　Peruzzi L,　Forzano S, et al. Presenting phenotype and clinical evaluation in a cohort of 22 Williams-Beuren syndrome patients. Eur J Med Genet. 2007;50:327-37.

4. Viana MM, Stofanko M, Gonçalves-Dornelas H, da Silva Cunha P, de Aguiar MJ. Phenotype of Williams-Beuren syndrome in Brazilian patients: comments on the article by Patil, et al. [2012] and discussion of variable phenotypes in distinct populations. Am J Med Genet A. 2013;161A:637-8.