Diagnosis of TET3‐Related Beck–Fahrner Syndrome in an Individual With Chorioretinal and Iris Colobomata Using a DNA Methylation Signature

Disorders of developmental delay can occur from pathogenic variants in genes responsible for epigenetic regulation. Heterozygous and biallelic pathogenic variants in TET3 have recently been described in TET3-related Beck-Fahrner syndrome (TET3-BEFAHRS), representing an autosomal dominant disorder with variable expressivity. Typical features include intellectual disability and developmental delay. Patients can also present with facial …