Novel Hemizygous Missense Variant of Spermine Synthase (SMS) Gene Causes Snyder-Robinson Syndrome in a Four-Year-Old Boy.

Abstract

Snyder-Robinson syndrome (SRS) is an extremely rare X-linked intellectual disability syndrome (MRXSSR; MIM #309583). The main clinical features of SRS include psychomotor delay, hypotonia, and asthenic-type body habitus - reduced body weight and bone abnormalities (osteoporosis, fractures, kyphoscoliosis). We report a case of SRS with a hemizygous missense variant in the SMS gene,c.334C>G (p.Pro112Ala), in a 4-year-old boy, who initially developed hypotonia, delayed motor skills, and subsequently epilepsy. This variant in SMS was found to be de novo. To the best of our knowledge, this novel SMS gene variant has never been previously reported in disease-related variation databases, such as ClinVar or HGMD.

• Authors: Stella Mouskou, Adamantios Katerelos, Artemis Doulgeraki, Sofia Leka-Emiri, Emmanouil Manolakos, Ioannis Papoulidis, Athina Ververi, Georgios Vartzelis, Anastasia Korona, Sotiria Mastroyanni, Konstantinos Voudris
• Journal: Molecular syndromology (Mol Syndromol) Vol. 12 Issue 3 Pg. 194-199 (Jun 2021) ISSN: 1661-8769 [Print] Switzerland
• PMID: 34177437 (Publication Type: Case Reports)
• Copyright: Copyright © 2021 by S. Karger AG, Basel.