Clinical symptoms of seven Japanese patients with Potocki-Lupski syndrome

Abstract

  Objective: The deletion of 17p11.2 region is well known as the cause of Smith-Magenis syndrome (SMS) ; however, Potocki-Lupski syndrome (PTLS) caused by the duplication of the same region is not well understood in Japan. In order to clarify the actual situation of Japanese patients with PTLS, we report on the clinical information of patients diagnosed with our ongoing study. Methods: Clinical information of patients with 17p11.2 duplications, who were diagnosed by comprehensive genome copy number analyses, were compared with previously reported overseas patients. Results: Duplication of 17p11.2 region was observed in seven patients (male/female=2/5, age : 1 year 5 months to 5 years 11 months). All patients displayed psychomotor developmental delay and non-specific facial features. Hypotonia and symptoms related to autism spectrum disorder such as stereotype movements were observed in four patients, and epilepsy was found in two patients. Therefore, the phenotypic characteristics of all patients in this study were consistent with those previously reported in PTLS patients. Conclusions: SMS is relatively easy to distinguish from co-existence of congenital heart disease and characteristic facial features ; however, seven Japanese patients with PTLS identified in this study showed non-specific clinical features such as psychomotor developmental delay, hypotonia, and behavioral abnormalities. Therefore, it would be difficult to identify PTLS just based on such clinical information. We consider that it is necessary to accumulate further information on patients with PTLS for a better understanding of this syndrome.