INTRODUCTION: Rubinstein-Taybi syndrome (RSTS) is one of the many forms of syndromic intellectual disability, occurring in the population with a frequency of 1: 100-125 thousand newborns. The specific phenotype of patients enables the so-called "portrait" diagnosis of classical cases of RSTS, followed by the analysis of the METHODS: In this paper we present the results of a study of 158 Russian patients referred for molecular diagnosis of RSTS using multiplex ligation-dependent probe amplification (MLPA) and next-generation sequencing (NGS). RESULTS: Pathogenic and likely pathogenic variants were identified in 67 patients (42.4%), of which 62 (39%) were in