Severe phenotype in two half-sibs with Adams Oliver syndrome

Adams Oliver syndrome (AOS) is a highly variable entity with terminal transverse limb defects (TTLD) and aplasia cutis congenita (ACC) with a wide phenotypic spectrum. Several inheritance models have been observed; the most severe phenotype has been related to an autosomal recessive (AR) pattern of inheritance. OBJECTIVE. To present a family with two half siblings with a severe phenotype of Adams Oliver syndrome in which the mother was healthy. A 27 year-old woman was referred to the Genetics Department. Her previous girl presented acrania, constriction rings and terminal transverse limb defects. The present girl had occipital encephalocele, large scalp defects, aplasia cutis congenita, terminal transverse limb defects and bilateral cleft lip and palate. Autosomal dominant inheritance with reduced penetrance or gonadal mosaicism has to be considered in Adams Oliver syndrome with severe intracranial anomalies.