Summary: HDR is a rare autosomal dominant genetic disorder characterized by the triad of hypoparathyroidism, sensorineural deafness and renal anomalies caused by haploinsufficiency loss of function of the GATA-binding protein 3 (GATA3) gene. We present a case of a 56-year-old male diagnosed with hypoparathyroidism, sensorineural deafness, renal hypoplasia and epilepsy. Genetic testing revealed a novel GATA3 heterozygous mutation c.860C>A with a predicted amino acid substitution p.Ala287Asp. This hitherto unreported missense GATA mutation was characterized by a relatively late-onset and milder phenotype of the HDR triad.
Learning points: GATA3 gene mutations located on chromosome 10p cause haploinsufficiency of the GATA3 protein affecting fetal development of the parathyroid glands, inner ear and renal anomalies, resulting in HDR syndrome with an autosomal dominant inheritance pattern.Also known as Barakat syndrome, it has been reported in less than 200 cases with an identified mutation, each having a varied phenotypic presentation without consistent genotypic correlation.We present a patient with HDR syndrome who tested positive for a novel mutation c.860C>A, resulting in a missense substitution of amino acids p.Ala287Asp in the GATA3 gene.Clinicians who identify this rare triad of hypoparathyroidism, sensorineural deafness and renal anomalies should further investigate with genetic testing for GATA3 mutations.
Keywords: Barakat syndrome; GATA3 mutation; HDR syndrome; ZF1; familial hypoparathyroidism; sensorineural deafness; zinc finger transcription factor.