Human ABL1 deficiency syndrome

A multiple congenital anomalies/dysmorphic syndrome caused by homozygous loss-of-function variants in the ABL1 gene. It is characterized by multiple congenital malformations (wormian skull bones and brachydactyly) and distinctive facial dysmorphism (hypertelorism, prominent eyes, short, broad and flat nose, and macrostomia). It is allelic to, but clinically distinct from, congenital heart defects and skeletal malformations syndrome, which is caused by germline gain-of-function variants in ABL1.