Phenotypic variability in 49 cases of <i>ESCO2</i> mutations, including novel missense and codon deletion in the acetyltransferase domain, correlates with <i>ESCO2</i> expression and establishes the clinical criteria for Roberts syndrome

Abstract

Using the cohort of 49 patients, the clinical criteria for RBS were delineated to include: growth retardation; symmetric mesomelic shortening of the limbs in which the upper limbs are more commonly and severely affected than the lower limbs; characteristic facies with microcephaly. The severity of malformations of the facies correlates with the severity of limb reduction. The occurrence of corneal opacities may be associated with specific mutations. Two new mutations, both in the ESCO2 acetyltransferase domain, are described and their acetylation effects in vitro demonstrated. In situ hybridisation on human embryos showed ESCO2 expression in the brain, face, limb, kidney and gonads, which corresponds to the structures affected in RBS.