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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.

SUBMITTER: Mouskou S

PROVIDER: S-EPMC8215975 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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

Mouskou Stella S Katerelos Adamantios A Doulgeraki Artemis A Leka-Emiri Sofia S Manolakos Emmanouil E Papoulidis Ioannis I Ververi Athina A Vartzelis Georgios G Korona Anastasia A Mastroyanni Sotiria S Voudris Konstantinos K

Molecular syndromology 20210419 3

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 subs ...[more]

PMID: 34177437

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