Confirmation of EP300 gene mutations as a rare cause of Rubinstein-Taybi syndrome.

The Rubinstein-Taybi syndrome (RSTS, MIM 180849), a dominant Mendelian disorder with typical face, short stature, skeletal abnormalities, and mental retardation, is usually caused by heterozygous mutations of the CREBBP gene, but recently, EP300 gene mutations were reported in three individuals. Using quantitative PCR (for the CREBBP and EP300 genes) and genomic sequencing (for the EP300 gene), we studied here 13 patients who had shown no mutation after genomic sequencing of the CREBBP gene in a previous investigation. Two new disease-causing mutations were identified, including a partial deletion of CREBBP and a 1-bp deletion in EP300, c.7100delC (p.P2366fsX2401). The 1-bp deletion represe…