Goldenhar Syndrome and Oculo-auriculo-vertebral spectrum (GS/OAVS): clinical, citogenomic and molecular study

Abstract

Goldenhar syndrome was characterized as an association of external ear deformities, facial asymmetry, epibulbar dermoid and vertebral changes. Its etiology is multifactorial, but familial cases have been described, with autosomal recessive, autosomal dominant, variable expressivity and incomplete penetrance. Several chromosomal abnormalities have also been described, associated with the syndrome, and the chromosomes most frequently involved are chromosome 22 (Deletion (Del) and duplication (dup) and trisomy of the long arm), chromosome 5 (del short arm and translocation between chromosomes 5 and 8) and chromosome 18 (Del, and recombinant trisomy). Goldenhar syndrome was associated with risk factors such as vasoactive drugs during pregnancy, bleeding in the second trimester, maternal diabetes, multiple pregnancies. For some authors, microtia, hemifacial microsomia and Goldenhar syndrome phenotypes characterizes oculoauriculovertebral spectrum (OAV), within the group of syndromes developing first and second arches. For others, the OAV spectrum understand Goldenhar syndrome with changes in other organs or systems, the most common, cardiovascular (50%), central nervous system or mental impairment (5 to 10%) and renal / respiratory (5% ). The risk of recurrence of the OAV spectrum, for first-degree relatives, is 6%. The accuracy of clinical diagnosis in SG / OAVS is a challenge for clinical geneticists, since this group of patients has a high phenotypic variability, genetic heterogeneity and overlap between the clinical features. To date, no specific gene has been identified for OAVS. The systematic use, however, of molecular genetics research has identified in these patients regions of CNV and consequently genes likely involved with the syndrome like YPEL1 and ERK2 genes on chromosome 22q.