MED13 encodes a component of the Mediator complex, a multiprotein transcriptional coactivator complex universally expressed in eukaryotes and required for gene expression. Mediator is a large multi-protein complex organized in head, middle and tail, joined with a kinase module. Specifically, MED13 encodes a subunit of the Mediator kinase module regulator.
Mutations in MED13 are rare and usually occur de novo although an autosomal dominant inheritance has been reported.
To date, 22 variants have been described, consisting of missense/nonsense variants and small/gross deletions.
Patterns of variation in MED13 in the GnomAD database indicate that MED13 is relatively intolerant to loss-of-function variation; notwithstanding the molecular mechanism of pathogenicity is still debated, particularly for truncating variants.
Genetic testing
Mutations in MED13 can be identified using either direct sequencing of the MED13 gene or by genome/exome sequencing.