An Adult Goldenhar Syndrome Patient With a Mosaic Small Su-Pernumerary Marker Chromosome (sSMC) Identified As Ring Chromosome 19

Goldenhar Syndrome (GS), also known as oculoauriculovertebral spectrum (OVAS), is a rare congenital condition characterized by impaired development of structures such as ears, eyes, nose, palate, lip, mandible, maxilla, and teeth. The etiopathogenesis is multifactorial and dependent on genetic and environmental factors, yet the syndrome has many unknowns. We report a case of a 31-year-old male diagnosed clinically with GS as an infant with an absent left ear, hearing loss, absent left lung lobe, reduced growth of left upper limb, decreased size of left face, absent left kidney, and a missing left thumb, who was seen in the genetic clinic for prenatal genetic counseling. A microarray comparative genome hybridization (aCGH) was performed for copy number abnormalities and targeted NGS panels were performed for hereditary hearing loss and limb/digital malformations. aCGH revealed a 471kb loss at 16p12.2 and a mosaic 7.3Mb gain at 19p12q12. Metaphase FISH confirmed the orientation of 19p12q12 gain as small supernumerary ring chromosome 19. NGS revealed multiple variants (MYH14 c.4001C>T, PDE1C c.8C>T, ADGRV1 c.15502A>G, CDH23 c.8772C>A, MYO3A c.484G>A, ADAMTS10 c.506G>A, CHUK c.1294C>T, CSPP1 c.1972A>G, and TCTN2 c.160G>A). Due to the heterogeneous clinical manifestation and genetic heterogeneity of GS, a comprehensive genetic testing strategy is needed for timely diagnosis and better patient care.