ERF and congenital rubella syndrome: In our recent investigation using the target sequencing panel for 34 CRS-related genes, we observed that individuals with rare or structural variations in causative genes accounted for up to 30% of CRS patients in a Korean cohort (6), including incomplete penetrance in the haploinsufficiency genes that are associated with autosomal dominant disorders, such as ERF and TCF12 (7, 8).