Abstract
Background Adams-Oliver syndrome (AOS) is a rare, inherited multi-systemic malformation syndrome characterized by a combination of aplasia cutis congenita and transverse terminal limb defects along with variable involvement of the central nervous system, eyes, and cardiovascular system. AOS can be inherited as both autosomal-dominant and recessive traits. Pathogenic variants in theDOCK6, ARHGAP31, EOGT, RBPJ, DLL4, andNOTCH1genes have been associated with AOS. Purpose To report a novel homozygous variant in theDOCK6gene associated with Adams-Oliver syndrome type 2. Materials and methods Case report. Results We report a case of a 4-month-old male who presented with microcephaly, global developmental delay, truncal hypotonia, and limb reduction defects. Ophthalmic examination revealed bilateral nystagmus and retinal detachment with mild cataractous changes in addition to retrolental plaque in the left eye. Next generation sequencing analysis identified a novel homozygous frameshift likely pathogenic variant (c.1269_1285dup (p.Arg429Glnfs*32)) in theDOCK6gene. The constellation of the clinical findings and the genetic mutation were consistent with a diagnosis of AOS type 2. Conclusion The discovery of this new likely pathogenic variant enriches the genotypic spectrum ofDOCK6gene and contributes to genetic diagnosis and counseling of families with AOS. Neurologic and ocular findings appear to be consistent with AOS type 2 for which multidisciplinary clinical evaluation is crucial.