The first familial case of inherited intellectual developmental disorder with dysmorphic facies and behavioral abnormalities (IDDFBA) with a novel FBXO11 variant

Abstract Intellectual developmental disorder with dysmorphic facies and behavioral abnormalities (IDDFBA) caused by germline de novo variants in FBXO11 was recently recognized as a novel intellectual disability (ID) syndrome through reverse phenotyping after whole‐exome sequencing (WES). Fewer than 50 disease‐causing de novo FBXO11 variants in IDDFBA are reported thus far. Here, we present the first report of a family showing autosomal dominantly inherited IDDFBA, harboring a novel heterozygous variant in FBXO11 (c.2401_2405dup;p. Gly803Leufs*6) identified by WES. In this family, the mother and two daughters showed mild ID and mild facial dysmorphism. This finding is expected to increase our understanding of the genotype–phenotype of IDDFBA and to facilitate genetic counseling for the disorder caused by FBXO11 .